HomeMy WebLinkAbout2012-11-12 PACKET 07.B.City of
Cotta Grove
J Minnesota
To: Parks, Recreation and Natural Resources Commission
From: Zac Dockter, Parks and Recreation Director
CC:.
Date: November 5, 2012
Subject: River Oaks Scenic Overlook Natural Resources Management Plan
Background
The City has been working with the Friends of the Mississippi organization to develop a natural
resources management plan for the City owned property entitled "River Oaks Scenic Overlook ". This is
plan was largely funded through grant funding available from FMR. Attached with this memo is the final
report for approval.
Recommendation
Recommend the City Council to accept and place on file the River Oaks Scenic Overlook Natural
Resources Management Plan.
River Oaks Park
i r
0
Prepared by:
Joseph Walton
Friends of the Mississippi River
360 North Robert Street, Suite 400
St. Paul, MN 55101
Ph: 651 - 222 -2193 x33
November 2012
Friends of the Mississippi River 1 River Oaks Park NRMP
Natural Resource Management Plan
This Natural Area Management Plan and Work Plan has been
reviewed and approved by:
Landowner
Date:
Zac Dockter, Parks and Recreation Director, City of Cottage Grove, MN
Friends of the Mississippi River 2 River Oaks Park NRMP
Table of Contents
INTRODUCTION ........................................................................................... ..............................5
SITE INFORMATION .................................................................................... ..............................8
LANDSCAPE CONTEXT ............................................................................. .............................10
SITE GEOLOGY AND GROUNDWATER ........................................................... .............................13
SOILS AND TOPOGRAPHY ................................................................................. .............................14
RARESPECIES ....................................................................................................... .............................18
HISTORIC VEGETATION ..................................................................................... .............................18
HISTORIC AND EXISTING LAND USE ............................................................. .............................21
WATERRESOURCES ............................................................................................ .............................21
Groundwater Recharge and Infiltration Areas ................................................... .............................21
Stormwater Management Issues ............................................................................. .............................21
ECOLOGICALTHREATS ...................................................................................... .............................22
BluffPrairie ....................................................................................................................... .............................22
Forestand Woodland ................................................................................................... .............................22
ADJACENT LAND USE .......................................................................................... .............................23
Viewshedand Soundshed ........................................................................................... .............................24
GolfCourse ........................................................................................................................ .............................24
SmokeDrift and Neighbors ........................................................................................ .............................24
Tree Disease: Oak Wilt, BOB, etc .............................................................................. .............................25
EXISTING LAND COVER & ECOLOGICAL MANAGEMENT RECOMMENDATIONS
26
Oak Woodland - Brushland (0.99 ac), Oak Forest (0.57 ac), and Altered, Non - Native
Mixed Woodland (0.13 ac) (Total of 1.69 acres) .............................................. .............................31
Dry Prairie Bedrock Bluff Subtype (0.41 ac) ....................................................... .............................34
RESTORATION PROCESS ................................................................................... .............................39
RestorationGoals ........................................................................................................... .............................39
TargetPlant Communities .......................................................................................... .............................40
RestorationProcess ....................................................................................................... .............................41
Site -Wide Invasive Woody Plant Removal / Control ......................................... .............................42
RestorationPriorities ................................................................................................... .............................42
Prescribed Burns —More Information .................................................................. .............................45
Long -Term Monitoring and Maintenance ............................................................ .............................46
RESTORATION SCHEDULE AND COST ESTIMATES .................................. .............................47
WORKPLAN ............................................................................................... ...............................
50
InformationSources ............................................................................................ ..............................1
APPENDIX A Plant Species Recorded at the River Oaks Park Property ..........................1
APPENDIX B Plant Species for Restoration at River Oaks Park Property ......................1
Appendix C. Methods for Controlling Exotic, Invasive Plant Species . ..............................1
Appendix D. Ecological Contractors ............................................................... ..............................1
Friends of the Mississippi River 3 River Oaks Park NRMP
Figures
1. Natural Easement Map
2. Landscape Context Map
3. Landscape Context Map, Close -up
4. Surficial Geology Map
S. Soils and Topography Map
6. Soils and Topography Map, Close -up
7. Pre - settlement Vegetation Map
8. Historical Aerial Photo, 1936
9. Historical Aerial Photo, 1964
10. Historical Aerial Photo, 2010
11. Adjacent Landuse, Aerial Photo, 2010
12. Ecological Subsections Map
13. Existing Landcover Map
14. Existing Landcover Map, Close -up
15. Existing Landcover Map, with Notable Features
16. Target Plant Communities Map
Tables
1. Soils and Topography
2. Restoration Target Plant Communities for Existing Landcover
3. Restoration Schedule and Cost Estimates
4. Long -Term Management Schedule and Cost Estimates
S. Workplan
Friends of the Mississippi River 4 River Oaks Park NRMP
INTRODUCTION
This Natural Resource Management Plan presents the site analysis and
recommended management and land use activities for the 2.1 -acre natural area
called the River Oaks Park property. This document can be changed only by the City
of Cottage Grove.
The River Oaks Park property is owned by the City of Cottage Grove, Minnesota.
This site is located just south of Highway 61, and lays on the northern bank the
Mississippi River. It is a small parcel that serves as access to the river for the city.
The northern part of the parcel is wooded and relatively flat. The southern part of
the parcel is steep and has exposed bedrock and sheer cliff faces and is covered by
bedrock bluff prairie. The River Oaks golf course is to the northwest, to the east is
an agricultural field, and to the west is a newer large -lot residential housing
development. Railroad tracks exist at the base of the cliffs /steep slope, which
follows the contour of the river.
This property lies within a site that was identified as containing "high biological
diversity" by the Minnesota Department of Natural Resources (Figure 1). This
designation was most likely due to the presence of the dry bedrock bluff prairie. In
fact, the most notable feature of this property is that it contains a remnant bluff
prairie. Bluff prairies are native plant communities that occur on south and
southwest facing bluff slopes (sometimes called "goat prairies ") all along the
Mississippi River throughout southeastern Minnesota. The prairie on this parcel
actually represents the easternmost portion of a more extensive segment of bluff
prairie that extends to the west along the bluff crest. Today, the bulk of this bluff
prairie lies on privately owned land, at the rear of the lots of the new housing
development. A quick visual assessment proved that much of the bedrock prairie
still occurs along the ridgetop, but no in -depth assessment was done past the city -
owned property boundary.
This bluff prairie, technically called a Southern Dry Prairie - Bedrock Bluff Subtype,
UPs13c, was noted as part of an "element occurrence" by the Minnesota County
Biological Survey (MCBS) in 1987, and was ranked with a B indicating "good
estimated viability" and had a State -rank of "S3". The native plant community (NPC)
types and subtypes recognized in Minnesota have been assigned conservation status
ranks that reflect the risk of elimination of the community from Minnesota. There
are five ranks:
S1= critically imperiled
S2 = imperiled
S3 = vulnerable to extirpation
S4 = apparently secure; uncommon but not rare
S5 = secure, common, widespread, and abundant
These ranks are determined using methodology developed by the conservation
Friends of the Mississippi River 5 River Oaks Park NRMP
organization Nature Serve and its member natural heritage programs in North
America. S -ranks were assigned to Minnesota's NPC types and subtypes based on
information compiled by DNR plant ecologists on: 1) geographic range or extent; 2)
area of range occupied; 3) number of occurrences; 4) number of good occurrences,
or percent area of occurrences with good viability and ecological integrity; 5)
environmental specificity; 6) long -term trend; 7) short -term trend; 8) scope and
severity of major threats; and 9) intrinsic vulnerability.
Notes from the MCBS record, from 1988, describe this prairie to be in fairly good
condition: "open bluff prairie just above Soo Railroad on limestone, mid -slope with
10% outcrops and scattered bur oak savanna trees; dominant graminoids are side
oats grama, Kentucky blue grass, prairie dropseed, plains muhly grass, little
bluestem, and porcupine grass occasional; moderate forb diversity with relative
abundance of common species (Liatris, Petalostemum, Solidago, Helianthus); obvious
signs of disturbance are absent, some encroachment of pin oak, sumac on crest." In
1998, a Natural Resource Inventory of City of Cottage Grove, done by Bonestroo
Company, depicted the bluff prairie as more degraded than it was just ten years
before in 1988: "community 27C is moderate to low quality dry bedrock bluff
prairie... dominated by Kentucky bluegrass and smooth brome, however native
grasses such as little bluestem and side oats grama are present throughout the
community. The forb diversity is relatively low compared to most of the bluff
prairies in this area, with dominant species consisting of harebell, stiff goldenrod,
false boneset, and thimbleweed. Introduced grasses and invasion by woody species
is a major problem in this prairie. It appears that this prairie will slowly be taken
over by nonnative species unless management efforts are undertaken."
The rest of the site was comprised of degraded and overgrown woodland and oak
savanna. Several large, scattered savanna bur oaks were noted on the southeastern
portion of the parcel, but they were surrounded by a dense growth of woody brush,
with many nonnative shrubs (common buckthorn and Tartarian honeysuckle). The
northern neck of the parcel contains what appears to be a dry creek bed (ephemeral
stream) along the first third of its extent. There was a trail that led from the street
on the northern property boundary to the prairie opening on the bluff crest. At the
time of the writing of this document, this trail was recently cleared of woody brush
(buckthorn). The brush stumps must have been treated with chemical, since no
resprouting has occurred.
This site is located within the "St. Paul Baldwin Plains and Moraines" ecological
subsection (Figure 12). Although it is a very small parcel, this could serve to
provide habitat for wildlife species, especially if managed in conjunction with the
adjacent private lots to the west. Species of Greatest Conservation Need (SGCNs)
are defined as animal species whose populations are identified as being rare,
declining, or vulnerable in Minnesota or are declining in a substantial part of their
range outside of Minnesota (MN DNR, 2006. Tomorrow's Habitat for the Wild and
Rare). Habitat loss and degradation has been the primary causes of problems for
SGCN species in the subsection, with prairie, oak savanna, and grassland currently
Friends of the Mississippi River 6 River Oaks Park NRMP
containing the most species, so this property has the potential for conservation
value in the region. The DNR recommends that efforts be made to stabilize and
increase SGCN populations in oak savanna and prairie areas by managing invasive
species, using prescribed fire and other practices to maintain savanna and prairie, to
encourage restoration efforts, to manage grasslands adjacent to native prairie to
enhance habitat, and to provide technical assistance and protection opportunities to
interested individuals and organizations. These are also the top priorities of this
management plan.
The site is quite small, and is very long and narrow with lots of edge, and thus, on its
own is not of great ecological significance. However, the backs of the lots of the
adjacent private properties to the west of River Oaks Park also contain bedrock bluff
prairie. The parcel southeast of the park also contains diverse natural communities
and warrants protection and habitat management. If these private properties were
to be managed together with River Oaks Park, they would collectively make more of
an ecologically significant impact.
The purpose of this management plan is to:
Identify the existing ecological conditions on the property
Identify best management practices to maximize wildlife values, and retain
and improve water quality and increase community diversity
Document allowable uses and activities of the property
Specific ecological and cultural goals for this property are to:
• Increase coverage and diversity of native plant species and reduce non-
native species
• Provide connectivity with other natural areas in the landscape and along the
river corridor
• Maintain and manage the property for water quality by controlling runoff
and nutrient loading
• Create a model for responsible private land stewardship
• Enhance and expand the ecological functions of the property
Friends of the Mississippi River 7 River Oaks Park NRMP
SITE INFORMATION
Owner name, address, city /township, county and phone:
City of Cottage Grove, Minnesota
7516 80th Street South
Cottage Grove, MN 55016
Contact Person: Zac Dockter, Parks and Recreation Director
651- 458 -2808
Township, range, section:
T27N, R21W, Section 35, SE 1 /4, NE 1 /4.
Acres: 2.1
Watershed: Mississippi River
Watershed District: Lower St. Croix River
Parcel Identification Numbers:
163- 3502721410003
Natural Area Conservation Easement:
2.13 acres to be held by the City of Cottage Grove (Figure 1)
Element occurrence: There is one element occurrence on the property, which is
not a specific species but rather an entire assemblage of them, a community. The
community is called "Dry Bedrock Bluff Prairie (Southern) and it's Native Plant
Community Code is UPs13c. This occurrence was recorded in September 1988 by
Minnesota County Biological Survey staff (J. C. Almendinger and E. J. Cushing) from
the Mn DNR. It was ranked as "B = good estimated viability" and its State -Rank was
"STY.
Friends of the Mississippi River 8 River Oaks Park NRMP
Figure 1. Natural Area Easement
Friends of the Mississippi River 9 River Oaks Park NRMP
1:30,000 Data Source: MN DNR Data Deli
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parcels wash 0.5 0.25 0 0.5 Miles A
NI,
LANDSCAPE CONTEXT
Proximity to established greenways
The River Oaks Park property lies within the Metro Conservation Corridors (MeCC),
a regional landscape conservation plan of the DNR (Figures 2). Besides its
ecological value, being within the McCC enables the site to be eligible for potential
funding from the State of Minnesota.
River Oak Park is also part of Mississippi National River and Recreation Area
(MNRRA), a unit of the National Park Service, which encompasses the Mississippi
River corridor within the Twin Cities Metropolitan Area. The site is also located
within an Important Bird Area, a global designation of Audubon Society, due to its
importance as a migratory bird corridor
Figure 3 shows the context of River Oaks Park within the local landscape. This map
illustrates the fact that the park is somewhat isolated from other open space areas,
but could be potentially connected via a corridor through the golf course to Cottage
Grove Ravine Regional Park. This map also shows the importance of the privately
owned lands that border the north side of the river, near the park. These private
lands contain most of the best examples of bio- diversity in the local area.
Also nearby (approximately 1800 ft to the west, along the river bluff) is property
owned by 3M Corporation - -3,000 acres, much of it natural, and containing a sand -
gravel savanna remnant. River Oaks is close enough that the 3M land could be
important for providing habitat to the some species.
Ecological significance and wildlife value
River Oaks Park is included in an area that was delineated by the Minnesota DNR as
having high significant biodiversity. They compared many natural and open space
sites across the county to develop this ranking as part of the Minnesota County
Biological Survey that started in the 1980's. This ranking was based on the remnant
bluff prairie. Not much prairie remains in this ecological subsection (St. Paul
Baldwin Plains and Moraines), so it is important to protect, restore, and, if possible,
expand every remnant (MN DNR, 2006. Tomorrow's Habitat for the Wild and Rare).
Larger tracts of land make more valuable habitat for most species of wildlife.
Engaging the nearby private landowners so that the bedrock bluff prairie remnants
on their land can be protected and /or managed together as a contiguous unit with
the park property would be advantageous to wildlife populations. This is especially
true since the parcel of land that makes up this park is so small, and also because it
is fairly isolated from other public natural areas.
Friends of the Mississippi River 10 River Oaks Park NRMP
FIGURE Z. LANDSCAPE CONTEXT
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Friends of the Mississippi River 11 River Oaks Park NRMP
[GORE 3. LANDSCAPE CONTEXT, CLOSE UP.
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Friends of the Mississippi River 12 River Oaks Park NRMP
SITE GEOLOGY AND GROUNDWATER
The surficial geology of the site consists of two main types: dissected bedrock
terranes and Superior Lobe deposits (Figure 4). The dissected bedrock, which
occupies the majority of the site, is St. Peter sandstone of middle Ordovician origin,
which is discontinuously exposed
and generally mantled by less than
five feet of sandy to rocky colluvium
and loess (Meyer, Baker, and
Patterson, 1990). The Superior
deposits are outwash sand and
loamy sand.
The Prairie du Chien contains the
primary aquifer that is used for
drinking water throughout the
region. Although not as close to the
surface as other bedrock formations
in this location, the sensitivity of the
Prairie du Chien groundwater
system to pollution is ranked as
high, since there is very little
confining layer between the surface
and the bedrock layer. High means
that contaminants will probably
reach the system in a matter of
weeks to years. This has heavy
implications on how management of
this site should proceed and on
what should be allowed and not
allowed on this site, in terms of potential pollution and contaminants.
Figure 4. Surficial Geology. The majority
of the site is underlain by dissected
bedrock. The north "neck" of the site is
underlain by Superior Lobe outwash
deposits.
Friends of the Mississippi River 13 River Oaks Park NRMP
iSedwit dwinated 1:7,500 Data Sou¢e: MN DNR Data Deh
Ouh Jsh 1,000 5W a 1.000 F-1
LTemee
SOILS AND TOPOGRAPHY
The soil types are summarized in Table 1 and illustrated in Figures 5 and 6. The
predominant soil types of the site are Mahtomedi Variant Rock Outcrop Complex
(1820F) and Sparta Loamy Sand, 2 to 15% slopes (813 and 8C). The loamy sands
occupy the flat, middle and northern parts of the parcel and the Rock Outcrop
Complex occupies the steep, southern portion. The letters in the code indicate the
percent slope, with B = 1 to 6 %, C = 6 to 12 %, D = 12 to 18 %, and F = 25 to 65%
slopes.
TABLE 1. SOILS & TOPOGRAPHY.
*ED = Excessively Drained * *HEL = Highly Erodible
Soil formation is the result of the interaction of five soil- forming factors: parent
material, climate, organisms, topographic position or slope, and time (Foth, 1990).
Taken collectively, these factors can help determine the dominant floral and faunal
communities that helped form the soils. The Sparta loamy sand soil unit is a
mollisol, which is a prairie soil. Mollisols are generally deep, dark in color, and rich
in cations, and thus would have been dominated by graminoid vegetation (prairie or
savanna) pre - settlement. In this case, however, since the soil is quite sandy, the
organic content, available nutrients, and water capacity are low, and thus-the soil is
very prone to erosion and drought. The Mahtomedi Varient is a sand - textured
entisol, which is a recently formed soil. This entisol would have been formed from
the weathering of the sandstone outcrops. The soil unit is actually a complex of
Mahtomedi Varient and Rock Outcrop from the exposed bedrock on the bluff.
There are no wetlands on this property or hydric soils. All of the soils on the
property are excessively well drained, and they do not pond or accumulate organic
matter. There is great potential for erosion, considering the steep slopes on the
property. Care should be taken to not denude these highly erodible slopes, or else
gullies can form and become unstable, and sediment washes downhill, eventually
reaching the river.. Maintaining herbaceous vegetation is the best way to prevent
erosion, since the fine roots of these types of plants hold onto the fine soil particles.
Friends of the Mississippi River 14 River Oaks Park NRMP
Hydric
Soil
Percent
(Yes
Drain-
Erod-
Code
Soil Name
Slope
Acres
Soil Family
or No )
age*
ibilit **
Mahtomedi
Varient -Rock
Outcrop
Mixed, frigid, Typic
1820F
Complex
25 to 65
0.69
Udi samments
N
ED
HEL
Sparta loamy
Sandy, mixed, mesic
8B
sand
2 to 6
0.71
Entic Ha ludolls
N
ED
HEL
Sparta loamy
Sandy, mixed, mesic
8C
sand
6 to 15
0.74
Entic Ha ludolls
N
ED
HEL
TOTAL ALL SOILS
2.14
*ED = Excessively Drained * *HEL = Highly Erodible
Soil formation is the result of the interaction of five soil- forming factors: parent
material, climate, organisms, topographic position or slope, and time (Foth, 1990).
Taken collectively, these factors can help determine the dominant floral and faunal
communities that helped form the soils. The Sparta loamy sand soil unit is a
mollisol, which is a prairie soil. Mollisols are generally deep, dark in color, and rich
in cations, and thus would have been dominated by graminoid vegetation (prairie or
savanna) pre - settlement. In this case, however, since the soil is quite sandy, the
organic content, available nutrients, and water capacity are low, and thus-the soil is
very prone to erosion and drought. The Mahtomedi Varient is a sand - textured
entisol, which is a recently formed soil. This entisol would have been formed from
the weathering of the sandstone outcrops. The soil unit is actually a complex of
Mahtomedi Varient and Rock Outcrop from the exposed bedrock on the bluff.
There are no wetlands on this property or hydric soils. All of the soils on the
property are excessively well drained, and they do not pond or accumulate organic
matter. There is great potential for erosion, considering the steep slopes on the
property. Care should be taken to not denude these highly erodible slopes, or else
gullies can form and become unstable, and sediment washes downhill, eventually
reaching the river.. Maintaining herbaceous vegetation is the best way to prevent
erosion, since the fine roots of these types of plants hold onto the fine soil particles.
Friends of the Mississippi River 14 River Oaks Park NRMP
Topography ranges from the high point of 860 feet above sea level, located on the
flat bluff top at the middle part of the property, to a low of approximately 720 feet
above sea level at the bottom of the bluff slope at the southeast corner —a difference
of 140 feet. Views of the river valley and surrounding landscape are quite stunning
from the high vantage point of the bluff crest. Managing the bluff part of the
property for prairie is important to maintain this outstanding vista.
There is a ravine or small creek bed (ephemeral creek) located in the northern
"neck" of the property. This creek was dry at the time of the visit by the ecologist in
April, 2012._It did appear that it carries meltwater or runoff from rain events.
Friends of the Mississippi River 15 River Oaks Park NRMP
Figure 5. Soils and Topography
8B = Sparta loamy sand, 2 -6% slopes
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Figure 6. Soils & Topography, close up.
190 95 0 190 Feet
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RARE SPECIES
The only recorded element of occurrence refers not to any particular species, but
rather to a group of them, namely the plant community (NPC) called "Dry Bedrock
Bluff Prairie (Southern) ", NPC code UPs13c. As stated in the introduction, this
occurrence was last observed in September 1988 by Minnesota County Biological
Survey staff (J. C. Almendinger and E. J. Cushing) from the Minnesota DNR. It was
ranked as "B = good estimated viability" and its State -Rank was "S3".
There is no record of any rare or state - listed species within this property (Figure 3),
and none were observed by the FMR ecologist during field surveys. However, there
may be some rare species present that were not yet found, thus it is recommended
to monitor for rare species, at different times of the year, so as to have a better
chance of potentially encountering them. Since the site is very small, the likelihood
of finding a rare species here is low. Within one mile of the site there were recorded
a number of element occurrences, but they were not for individual species, but
rather for plant communities. The plant communities recorded were Dry Sand
Gravel Prairie (UPs13b), another Bedrock Bluff Prairie (UPs13c), Oak- Woodland
(FDs37a), White Pin -Oak -Sugar Maple Forest Type (MHs38a), and Southern Wet
Cliff Class (CTs53).
HISTORIC VEGETATION
One of the best information
sources available on plant
communities that were present at
the time of European settlement
comes from the 1850's Public
Land Surveyor (PLS) notes, which
recorded plant species (usually
"bearing trees ") at each one -mile
node. A compilation of those
notes was converted into a map
showing the plant communities of
the entire state (Marschner 1974).
The region where the River Oaks
Park property is located was
designated as "Oak Openings and
Barrens" and was flanked by
regions of "Prairie" (Figure 7).
Oak openings and barrens is an
area that consisted of patches of
scrubby oaks and shrubs with
many prairie "openings ", similar
Figure 7. Pre - settlement Vegetation.
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to what we would today call savanna. Prairie was an area dominated by tall and
short- to medium -sized grasses and forbs (wild flowers), with patches of shrubs and
very few, to no trees. Note that the soils data and the pre - settlement vegetation data
concur - both point to prairie or savanna vegetation at this site. The nearest bearing
trees to the River Oaks site were at the north end, and were "black oak" and "bur
oak ". Black oak would be what we today call red oak or pin oak.
Historical aerial photos of the site were obtained from the Borchert Map Library in
Wilson Library on the West Bank of the University of Minnesota. Illustrated here
are three snapshots from the last % of a century, 1936, 1965, and 2010 (Figures 8,
9, and 10). It can be seen that the most striking change has been the gradual
increase in tree /shrub density across the landscape. There were some areas of
high- density trees /shrubs in the 1936 photo, but they occurred primarily in ravines.
The uplands, in 1936, were much more open, with only a few scattered trees —a
savanna landscape. The River Oaks parcel itself didn't change much from 1936 to
1964, but looking outside of that property clearly shows the progression of
increased tree /shrub density. The 2010 photo shows that, even in the River Oaks
parcel, trees /shrubs have significantly increased in density —the north portion of
the photo in particular. Given this trend, with no management of the site, the
southern end of the River Oaks Park will likely and eventually succeed to a dry
oak /buckthorn forest; hence the prairie would be lost.
Also note that the bedrock bluff prairie can be distinguished in the older photos.
The ridgetop has a line of trees that can be identified in the photo from 1964, and
even further back in time, from the 1936 photo. Also, in 1936 and 1964, the
savanna extended all the way northward up to the agricultural fields. In the 2010
photo, the only part of the landscape that is left open is this strip of bedrock prairie
on the bluff. Unfortunately, today it is fragmented by multiple private land
ownerships and roadways, which are challenging obstacles to the integrity of these
native communities.
Friends of the Mississippi River 19 River Oaks Park NRMP
Figures 8 and 9. Historical Photographs: 1936, 1964. Compare and contrast with
current photo from 2010 in Figure 10.
Friends of the Mississippi River 20 River Oaks Park NRMP
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I A,000 �`
500 250 0 500 Fcal A
HISTORIC AND EXISTING LAND USE
Historically, post- settlement, the northern portion of the site was probably used for
grazing, as can be deduced by the presence of smooth brome and by the low
diversity of native understory forbs and graminoids in the "woodland" today. The
southern portion probably didn't receive as heavy a grazing pressure, by virtue of its
steepness, and thus is in better condition today. In the recent past, the land was
probably either grazed or was left fallow. Today the land is a city park. No
amenities have been added to the park, in terms of benches, overlooks, signage, etc.
A trail is currently being roughed in— buckthorn has been removed. Also, the
property boundaries had been marked with plastic property posts. Access is
attained from Kingsborough Street to the north of the parcel.
WATER RESOURCES
There are currently no surface water features, except for the dry creek bed at the
north end of the parcel. It is possible that the runoff that created this creek
originates from the impervious surfaces (roads, houses, driveways, etc.) of the
development adjacent on the north side of the parcel. More data is needed to
confirm or deny this hypothesis.
Groundwater Recharge and Infiltration Areas
There are no wetlands, which are typically recharge or discharge areas to
groundwater, on this site, but may have moderately high recharge due to exposed
bedrock and thin soils.. It must be assumed, however, that since this site was rated
as "high" for sensitivity of the Prairie du Chien - Jordan aquifer to pollution (Balaban
and Hobbs, 1990), then potentially anywhere on this site could be a recharge or
infiltration area. There are many areas of potential groundwater recharge,
including the ravines, depressional areas on slopes, flat or level areas on the ridge
top, gradual slopes, etc. — basically anywhere water is directed or can slow down to
infiltrate through cracks in the rock or through soil. In the bluff prairie unit, there is
precious little soil material covering the bedrock, and thus very little protection to
the aquifer below. Chemicals should be avoided because of their potential affects on
groundwater in this sensitive area. If chemicals must be used during restoration
activities, extreme caution should be exhibited when handling and applying
chemicals. Spilling of chemicals could be very detrimental to the aquifer. No mixing
of chemicals or pouring of containers should be allowed on site. All mixing and
pouring should be done ahead of time and containers hauled into or out of the site.
Stormwater Management Issues
Due to the pervious and excessively well drained nature of the soils in this area, it is
conceivable that all of the runoff will eventually percolate along the length of this
parcel before it reaches the bedrock bluff prairie. Given the possibility of large rain
events causing significant amounts of surface runoff generated from nearby housing
developments, stabilization of the head and banks of the dry creek bed is
recommended. Stabilization refers to installing or positioning rocks and fibrous-
Friends of the Mississippi River 21 River Oaks Park NRMP
rooted plants along the creek channel and banks (Minnesota Soil Bioengineering
Handbook, 2006).
ECOLOGICAL THREATS
Bluff Prairie
The majority of the bluff prairie was covered with fine - rooted vegetation
(graminoids and forbs), but it was being invaded on the sides by woody vegetation
(shrubs and small trees).
It is well known that the fine roots of herbaceous vegetation is the primary factor
that holds fine soil particles in place, especially on steep slopes. Thus, a lack of
graminoids and forbs may likely lead to a situation of increased erosion and
sedimentation at the bases of steep slopes. In light of this, the fact that these slopes
were covered by graminoids and wildflowers is quite a remarkable benefit.
Restoration efforts on steep slopes are typically very difficult because seed tends to
wash away.
The majority of the rest of the site, although dominated by trees and shrubs, lies on
relatively flat terrain, except for the extreme southeast corner, which is on a steep
slope. Due to the flat topography, soil erosion is likely not to be much of a concern
other than potential runoff issues from impervious surfaces north of the parcel. The
major concern here is the dense growth of invasive exotic woody vegetation and the
lack of diversity in the shrub and ground layers (see Existing Conditions section and
Management Recommendations section).
Forest and Woodland
The forests and woodlands in this region have also been invaded by exotic
earthworms (Lumbricus terrestris, etc.), which have negatively impacted the soils.
Earthworm activity, contrary to popular opinion, is not good for the soil in
Minnesota because they are not native here. Tunneling into the top layers of soil
and ravenously consuming large amounts of leaf litter, their activities result in a net
soil compaction and a marked increase in the duff layer turnover rate (the time it
takes for the litter layer to be decomposed and turn into humus). Thus, where there
used to be several inches of light, fluffy duff layer in our native forests and
woodlands, now there is only a trace or often none at all, with compacted, bare soil
prevalent. This situation can then lead to detrimental impacts on surface water, due
to increased erosion and nutrient runoff from affected areas into nearby lakes and
streams.
Other threats are over - browsing from deer and lack of fire in the woodlands. White
tail deer can browse down much of the native flora, sometimes to the point of
extirpation. Fire, which would have been a common occurrence in these woodlands
pre- settlement, kills small to medium sized tree and shrub seedlings, thus reducing
Friends of the Mississippi River 22 River Oaks Park NRMP
overall canopy coverage, which allows more light to penetrate to the ground layer.
Reduced woody plant density, sparser canopy coverage, and increased light
penetration all tend to favor herbaceous vegetation. In the past, woodlands
contained a high diversity of grasses, sedges, ferns and forbs (wildflowers), which
today they generally do not, because of these various impacts just described. This
situation has developed over the course of the past 150 years and will not be easily
reversed. However, with proper, well -timed management, restoration of the River
Oaks Park property woodlands is possible and likely (see Management
Recommendations section below).
ADJACENT LAND USE
River Oaks Park is surrounded by both altered and natural lands (Figure 11). To
the east and southeast lies a 50- plus -acre parcel of natural forestland that is
privately owned. Directly to the south is a railroad. The railroad is very active. A
little further to the south is the Mississippi River. To the northeast is an agricultural
field. Directly to the west is a newer residential development consisting of twenty
to thirty large -lot homes. Beyond the homes to the northwest, is a golf course (River
Oaks Golf Course). Beyond to the north is Minnesota Highway 61.
Figure 11. Adjacent Landuse to River Oaks Park.
Adjacent land use has a huge
impact on the management of
River Oaks Park. Since the park
parcel is so small, the
surrounding land has a large
influence on the parkland.
Some restoration activities may
be rendered useless because of
the impact of the larger, nearby
adjacent land. For instance, if
buckthorn were to be cleared
from the small northern neck of
land on the north side of the
River oaks property, and it
were not cleared from the
adjacent lands on either side,
buckthorn seedlings would
quickly invade into the cleared
River Oaks zones, thus
reversing restoration efforts.
Another similar example, from
the bluff prairie, would be the
case of smooth sumac, which, if
controlled on the River Oaks
property but not on the
adjacent private lands to the
Friends of the Mississippi River 23 River Oaks Park NRMP
1:20.0W 0.1. S__ LINUA0�c"'
N
05 025 0 05 Ni'aS
1.,1;.Rhar Nk'Pa<k B_4.ry i AN
west, it would quickly advance into the cleared zone of the park, making
management more difficult and expensive. Thus, it will be important to reach out to
adjacent landowners to solicit the involvement of and coordinate management
efforts with River Oaks park, so as to make them lasting efforts and not temporary
ones. Also, a related benefit for collective management would be to make a larger
area of habitat for wildlife. Engaging the private landowners on all sides, especially
the homeowners to the west would enhance and expand the positive impacts of the
restoration efforts. Management of the park could be used as a model for the
surrounding landowners to emulate and copy. River Oaks Park, then, could be
viewed as a core habitat area from which private restoration and enhancement
activities could spread providing a larger positive result.
Viewshed and Soundshed
Views are spectacular from this property (Photos 11, 12). By virtue of its high
position on the landscape, both upstream and downstream directions afford
breathtaking views of the river and the surrounding bluffs and floodplains.
On the other hand, sounds in the area are not so spectacular. The proximity of the
railroad to the River Oaks property, and the high frequency of trains, makes for a
potentially loud, noisy experience for the park user. There is not much that can be
done to improve this situation, since the bluff prairie, the premiere feature of the
park, is located so close to the railroad tracks.
Golf Course
Activities from the golf course could potentially negatively impact the park, but the
intervening private homes between them would serve as a buffer. Turf
management activities such as broadcast herbicide applications onto the turf and
ornamentals could drift on wind currents, and negatively impact the park. Reaching
out to the staff of the River Oaks golf course, making them aware of the park and its
sensitivity to herbicide drift damage, is recommended. Likewise, drift from the
agricultural field, to the northeast, may be potentially damaging to plants in the
park, and outreach to the farmers or managers of these fields is recommended.
Smoke Drift and Neighbors
Burning the woodland and prairie of the park is a key management
recommendation of this plan. Reaching out to all adjacent landowners, discussing
the ramifications of fire and smoke that will emanate from the parkland, is
recommended. Talking with them regarding this issue could also be a good way to
start a discourse about other issues as well.
Friends of the Mississippi River 24 River Oaks Park NRMP
Tree Disease: Oak Wilt, BOB, etc.
There was an oak wilt infection center, located at the boundary of the bluff prairie
and the woodland that needs to be monitored.. Signs and symptoms of oak wilt
disease were observed in several northern pin oak trees. Since oak wilt disease,
caused by a systemic fungus, spreads underground between common root systems
of like species of oak (red or pin oak to other red or pin oaks, and white or bur oak
to other white or bur oaks), expect to continue to lose more pin oaks in the vicinity.
At present, bur oaks are still healthy, and efforts should be taken to prevent
overland spread of the disease to bur oaks. The best way to do that is to remove and
properly dispose of all infected red or pin oaks, which will prevent them from
sporulating.
Oak wilt is likely to be very difficult to control near the bluff prairie, given the thin
soils, prevalence of bedrock, and presence of steep slopes on the south end. Steady
and continued monitoring for this disease is recommended. Monitoring for oak wilt
starts in early summer, typically following the first shot of hot weather. Check for
sudden leaf -drop and for leaves that are discolored (drab olive green and /or with a
wedge of drab olive green in the center of the leaf). Also check for inter - veinal
chlorosis of leaves.
Control of oak wilt begins with preventing oaks from being damaged. Fresh wounds
attract beetles that vector the disease. To stop the progression of the fungus,
typically control consists of disrupting common root systems of trees so that the
fungus cannot spread from tree to tree. The most common method of root
disruption is to cut the roots around infected trees with a vibratory plow. Consult a
professional arborist or trees service that provides oak wilt control, on how to
proceed with treatment, if so desired.
Bur Oak Blight (BOB) could potentially be damaging too, so monitoring is
recommended. For Bur Oak Blight, one of the best ways to diagnose the presence of
this disease is by examining bur oaks during the winter —if they hold onto their
leaves (even just a few), this may indicate that they are infected with BOB.
Friends of the Mississippi River 25 River Oaks Park NRMP
EXISTING LAND COVER & ECOLOGICAL MANAGEMENT
RECOMMENDATIONS
A multi- agency group, led by the Department of Natural Resources (DNR),
developed a system called the Minnesota Land Cover Classification System (MLCCS),
which defines and classifies all types of landcover. This information was used as a
basis for the site evaluation, which was conducted by FMR's ecologist in the spring
of 2012. Recorded information included a list of plant species and their percent
coverage in each vegetation layer (tree, shrub, grass) (Appendix A), soil type,
slopes, and animal signs. Information also included ecological concerns, such as
erosion, exotic species, etc. The classification, used in this document, for landcover
units was modified as needed, based on plant species observed and the resulting
landcover types.
For determining target plant
communities for restoration
(Table 3), we considered the
historic conditions, existing
conditions, and relative effort vs.
benefits. As a guideline for the
target plant community goals, we
used the Field Guide to the Native
Plant Communities of Minnesota:
the Eastern Broadleaf Forest
Province (DNR, 2005). This book
describes the system developed
by the Minnesota Department of
Natural Resources for identifying
ecological systems and native
plant community types in the
state, based on multiple ecological
features such as major climate
zones, origin of glacial deposit,
deposition depth and distribution
patterns, dominant floral
structure and composition, and so
on. There are four ecological
provinces in Minnesota (prairie
parkland eastern broadleaf
St. Paul -
Baldwin Plains
)ds
x
v. A
m
A
o
Oak Savan
Rochester Plateau .
The
r Oak;
Ecological Subsection
1Anolu Sand Plain
elpwacas
Na s—rt. -' - -
-
IloMesterflaleau I 7'.400.000 Data source: MN Dr1R Dal, Deli
PausSaidaAn PWna 10 5 0 70 Miles
- ' a BlumaaMS__ —'_
N
forest, Laurentian mixed Figure 12. MN DNR Ecological Subsections map for
forest, and tallgrass aspen southeastern Minnesota. Red star shows approximate
parkland), ten sections within location of River Oaks Park property.
Friends of the Mississippi River 26 River Oaks Park NRMP
the provinces, and 26 subsections (Fig. 12). River Oaks Park property is classified as
follows:
Ecological Province: Eastern Broadleaf Forest
Ecological Section: Minnesota and Northeast Iowa Morainal
Ecological Subsection: St. Paul Baldwin Plains and Moraines
As stated earlier in the Historic Vegetation section, the vegetation of the River Oaks
property, in pre- settlement times was most likely bluff prairie on the bluffs, and oak
savanna on the rest of the property. This is still appropriate for the site, although
there has been some succession of communities towards forest and woodland.
Areas that had been oak savanna, at the time of European settlement, have today
succeeded to oak woodland.
Friends of the Mississippi River 27 River Oaks Park NRMP
Figure 13. Existing Landcover
Friends of the Mississippi River 28 River Oaks Park NRMP
Figure 14. Existing Landcover, close -up.
rver �n5 ram eouncary
'Altered/non-native mixed woodland
Dry prairie bedrock bluff subtype
Oak forest
Oak woodland- brushland
Friends of the Mississippi River 29 River Oaks Park NRMP
Figure 15. Existing Landcover with notable features and trails.
.,.-- •�._._ . _e...._.. .... ��..... 1:1,800
parcels A N s
10 -ft contours 200 100 0 200 Feet
Friends of the Mississippi River 30 River Oaks Park NRMP
The River Oaks Park property was evaluated by an FMR ecologist in early spring of
2012 and again in the third week of June, 2012. Recorded information included:
primary plant species and their relative coverage; animal signs; land use activities;
and ecological concerns such as erosion, exotic species, etc. Each of the land cover
units is shown in Figures 13 and 14 and described in the paragraphs below.
Photograph numbers refer to the locations, depicted on Figure 13. The landcover
classifications were based on the Minnesota Land Cover Classification System
(MLCCS) developed by the DNR (DNR 2005). The names of the cover types were
modified slightly for ease of use. Some notable features, such as interesting plant
specimens and geologic features, are illustrated in Figure 15. Also, please refer to
Figure 14, "Target Plant Communities ", throughout the following section.
Oak Wood land - Brushland (0.99 ac), Oak
Forest (0.57 ac), and Altered, Non - Native
Mixed Woodland (0.13 ac) (Total of 1.69
acres)
The Oak Woodland Brushland cover type
unit was located roughly in the center of
the property (Photo 1), on flat terrain, and
covers more area than any of the other
cover types on the property. In general,
though, for this property there are
virtually only two types of cover:
overgrown Oak Woodland - Brushland and
Dry Prairie Bedrock Bluff Subtype.
Moving either north or south along the
eastern boundary of the unit, the cover
14
.
Photo 1. View of oak forest at center of
property. Note the trail in the center of the
photo.
Friends of the Mississippi River 31 River Oaks Park NRMP
type grades into oak forest, where the canopy cover gets a little fuller and the trees
and shrubs get a little denser, therefore both the Oak Woodland- Brushland,the Oak
Forest, and the Altered Non - Native Woodland cover types will be lumped together
in this description, and will be referred to as Oak Woodland - Brushland (Photos 2
and 3).
"`" ""° °"" "" """ P „ "°"""'" UI "`° "a` °3 "' " important layer, since it
park.
influences, in large part, the other
layers beneath it. This layer
varied from 40% to 80% coverage. This layer was dominated by hardwoods;
medium- and large -sized bur oak and pin oak (6 to 28 inch DBH) were the dominant
Friends of the Mississippi River 32 River Oaks Park NRMP
The structure of the vegetation of the Oak
Woodland -Br (OW -Br) unit consisted of a
canopy tree layer, a sub - canopy tree layer, a
shrub layer, and a ground layer. The canopy
tree layer is generally the most
species (comprised over 50% of the trees). Bur oaks were the largest and oldest
hardwood species present. These bur oaks showed evidence of formerly being
more open grown, with many horizontal, lower branches (often dead, but were once
alive). Conifers were represented by only one species, redcedar, which was sub-
dominant. Other hardwood tree species present were quaking aspen (which was
found in clumps or stands), green ash, black cherry, hackberry, and boxelder. Trees
were more tightly spaced at the north end of the unit, and towards the south end,
they became sparser. The sub - canopy tree layer ranged from 40 to 60% coverage
and consisted primarily of pin oak, redcedar, quaking aspen, and green ash, with bur
oak constituting a lesser component. The shrub layer ranged from 20 to 50%
coverage and was dominated by common buckthorn (an exotic invasive shrub),
primarily, with Tartarian honeysuckle (another exotic) a strong second. Other
species found in the shrub layer were gooseberry species, chokecherry, and
raspberry species. The ground layer ranged from 10% to 40% coverage and was
quite low in diversity. The dominant plant, by far 80 -90% of this layer, was
common buckthorn (seedlings), with some areas being literally carpeted by small
buckthorn seedlings (Photo 4). Other species present in the ground layer were
Tartarian honeysuckle, raspberry species, motherwort (exotic), common burdock
(exotic, invasive), rue anemone, black snakeroot, catmint (exotic), Canada
goldenrod, Pennsylvania sedge, and Solomon's seal.
— The northern end of the unit, and
property, starts at Kingsborough
Trail. Southward from
Kingsborough Trail, this cover unit
consists of a narrow strip of land for
about 340 feet. A small, dry creek
runs through the middle of this
narrow strip. The property starts to
gradually widen, southward.
Photo 7. Woodland east of the bluff prairie.
Approximately 770 feet south of the
road, the property opens up onto the
bluff prairie. Extending through the
length of the woodland and ending at
the prairie opening was a foot trail
or path (Photo 1). Recently, this
path had been cleared of woody
vegetation. The workers had not Photo 8. Exotic woody vegetation choking out the
treated the stumps, however, as oak savanna near the bluff prairie.
shown by the lack of stump -
Friends of the Mississippi River 33 River Oaks Park NRMP
r . .
t
)
r
vegetation. The workers had not Photo 8. Exotic woody vegetation choking out the
treated the stumps, however, as oak savanna near the bluff prairie.
shown by the lack of stump -
Friends of the Mississippi River 33 River Oaks Park NRMP
sprouting in the spring (Photo 5), but they were vigorously re- sprouting in June.
Along the eastern boundary of the property, the woodland continues (Photo 7), all
the way down the slope, skirting the exposed bedrock bluff, and ending at the
railroad tracks below (Photo 6).
The woodland unit, although degraded by overgrazing and fire suppression, could
add increased habitat value if it were restored to oak savanna. The most urgent
priority is to control woody exotic brush (Photo 8). The next priority is to restore
the diversity of the shrub and ground layers of the property. Also, there was an oak
wilt infection center, located at the
boundary of the bluff prairie that needs to
be monitored. Management
recommendations in the following sections
help guide this potential restoration.
Birds observed were northern cardinal,
eastern blue jay, red -eyed vireo, and indigo
bunting.
Dry Prairie Bedrock Bluff Subtype (0.41 ac)
more simply known as "Bluff Prairie" unit was
the other prominent vegetation type present at
River Oaks Park (Photo 9). This cover type,
ecologically speaking, is the finest feature of
the property, since bluff prairie is rare in the
Ecological Subsection. Every effort should be
made to preserve and enhance this nice little
remnant. As would be expected, this unit was not dominated by trees and shrubs,
but by ground layer species (graminoids and forbs). The ground layer was
Friends of the Mississippi River 34 River Oaks Park NRMP
The Dry Prairie Bedrock Bluff Subtype, or
primarily continuous, with only some very small patches of bare soil. Also present
were scattered episodes of exposed
1 bedrock. The prairie vegetation was a
a +ti j
'�4 +'I mix of graminoids (grasses and sedges)
and (orbs (wildflowers), with
,. " • ;'?,, graminoids being more abundant than
forbs (about 2/3 graminoids to 1/3
forbs). Grasses were the dominant
graminoids, with both tall (big
bluestem, Indian grass, for example)
and medium -short grass (little
bluestem, side oats grama, hairy grama,
for example) species present and both warm (big bluestem, Indian grass) and cool
season (e.g., wild rye) species present. Forbs were fairly diverse, for such a small
prairie. Forbs present were bastard toadflax, harebells, leadplant, western
sunflower, sky -blue aster, columbine, western sunflower, black -eyed Susan, pasque
flower (Photo 10), grey goldenrod, purple prairie clover, hoary vervain, and
butterfly weed, etc. A complete list of existing plant species can be found in
Appendix A. Poison ivy, however, was not too abundant, as can be the case with
prairie remnants, which indicates that this area was perhaps never or only lightly
grazed, in the past. Fortunately,
there were not too many exotic
herbaceous weeds present. There
was a conspicuous patch of smooth
S
brome (about 15'x 25'), and exotic
1' invasive species, at the top of the
a t prairie, which should be controlled
(Photo 11).
The shrub layer was not terribly
robust, which is surprising,
considering the fact that no formal
management or natural fires have
occurred here in probably decades.
The dominant species was smooth
sumac, an aggressive native species.
Friends of the Mississippi River 35 River Oaks Park NRMP
Photo 12. Butterfly weed, Asclepias tuberosa,
in flower, June 21, 2012.
Photo 13. A Yellow - sulphur butterfly camouflages
nicely while feeding on a Yellow Sundrop,
Calylophus serrulatus.
On adjacent properties to the west, smooth sumac (and other shrub species as well)
was much denser (Photo 14), and thus the condition of the prairie was diminished,
since herbaceous species have difficulty competing with shrubby ones in the
absence of fire. Also present were poison ivy, redcedar, buckthorn, Tartarian
honeysuckle, and chokecherry (especially nearer the edges, close to the woodlands).
The bedrock cliffs contained a mix of herbaceous and shrubby species in between
the rocks and on ledges where soil had accumulated. A few small, scraggly bur oaks
were present in the prairie zone, too, but trees were uncommon. Also present were
native bittersweet vines.
Recently, a few large buckthorns have been removed from this prairie, as evidenced
by their stumps. To reiterate, the stumps were not treated, and thus they have since
re- sprouted (Photo 5a). Stumps should be treated with herbicide. Herbicide should
be applied in such a manner as to minimize the impacts to nearby plants. A good
method is to use a wick applicator. It is recommended that the removal of woody
plants should continue, expanding and improving this prairie remnant as much as
possible. Fire should also be re- introduced into this ecosystem to maintain its
health and integrity (see Management Recommendations below).
Vine Layer
Native bittersweet (Celastrus scandens) vine was found in a couple of scattered spots
in the bluff prairie, and at the base of the slope of the prairie at the bedrock cliff, just
above the railroad tracks. It is possible that Oriental bittersweet (Celastrus
Photo 16. Native bittersweet
orbiculatus) also occurs there (City Forester, (Photo by Paul Drobot).
personal communication, Oct., 2012). Since both species are very similar, it is
crucial to be able to correctly identify them, so that the native species is not
inadvertently removed or killed. The key difference between the species is in the
location of the inflorescence and fruit cluster. In the native, the inflorescence is
terminal, at the ends of branches, and has multiple flowers /fruits. In the exotic, it
arises from leaf axils, not the ends of the branches, and has fewer flowers /fruits per
cluster. Also, the leaves of the exotic tend to be rounder and the leaves of the native
tend to be narrower and pointier - -but overlap occurs, so this is a fuzzy
Friends of the Mississippi River 36 River Oaks Park NRMP
Photo 15. Oriental bittersweet
characteristic to go by. A less reliable character is also the color of the outer
covering of the fruit - -the native is more orange and the oriental is more yellow.
If the exotic, invasive Oriental bittersweet is present, it is highly recommended to
eradicate it. Cutting at the base with subsequent application of water -based
systemic herbicide is an effective method of control. For the native bittersweet, no
extra control measures need be taken; it is a valuable member of the plant
community and actually has become uncommon throughout its range. Native
bittersweet will be controlled naturally on the site, especially if the site gets burned.
Vistas
Spectacular vistas of the river and river valley are afforded from atop the bluff of
this park (Photos 17 and 18). If allowed to be encroached upon by tall, woody
vegetation, not only
would the bluff prairie
vanish, but also would
these incredible views.
Friends of the Mississippi River 37 River Oaks Park NRMP
Figure 16. Target Plant Communities at the River Oaks Park Property.
Each unit has a labeled acreage associated with it. Communities are shown in DNR code
(see map legend for code key)
Friends of the Mississippi River 38 River Oaks Park NRMP
RESTORATION PROCESS
Although this site is quite small, restoring native plant communities can be a
significant task. Assistance is available to help landowners with the process. Friends of
the Mississippi River and Washington County will continue to work closely with the
City of Cottage Grove, if desired, by helping to secure funding and providing project
management and oversight. Professional firms that can conduct management tasks
are listed in Appendix D.
Management recommendations were developed for each land cover area, with the
overall goals for the park area focused on 1) protecting and restoring high quality
bluff prairie, 2) restoring oak savanna, and woodland /forest, and 3) providing
wildlife habitat. Overall management practices to achieve those goals are:
• remove non - native, invasive, woody species;
• control non - native invasive herbaceous species, including, smooth brome
grass, reed canary grass, Canada thistle, common burdock, sweet clover,
spotted knapweed, bird's -foot trefoil, etc.;
• restore and expand the native ground layer and shrub layer on steeper
slopes, where it is currently lacking;
• conduct periodic prescribed burning to maintain and promote prairie,
savanna, and woodland vegetation and to reduce invasive shrubs and
overabundant tree seedlings;
• monitor annually for potential erosion and sedimentation, as well as for non-
native invasive woody species;
• institute a monitoring plan to track effectiveness of management and
restoration activities.
Restoration Goals
The primary objective for this site is to improve the composition of the plant
communities throughout the property to better reflect the diversity, composition
and structure that would have been present at the time of European settlement and
to improve the ecological functions that the historic native plant communities would
have provided, including:
• habitat for a diversity of wildlife species,
• nutrient and water cycling,
• carbon storage,
• moderation of water -table levels,
• erosion control,
• filtration of nutrients, sediments and pollutants,
• development and enrichment of soils,
• local temperature moderation.
Friends of the Mississippi River 39 River Oaks Park NRMP
In addition to the ecological values these restoration goals will also provide
community benefits by providing residents with an example of native communities
and spectacular views of the Mississippi River valley.
Though degraded by past uses, the existing plant cover retains a good variety of
native species and could be readily improved. A healthy and diverse plant
community can provide much greater wildlife value than a degraded one, and tends
to be much more stable, and less susceptible to disease, invasive species, and other
concerns.
Target Plant Communities
The restoration sites on this property will consist primarily of a mix of woodland
plant communities and native bluff prairie community.
The restoration target communities for this property are listed in Table 2 and
mapped in Figure 16.
Table 2. Restoration tar et plant communities for existing landcover.
TOTAL 2.11
As can be seen from Figure 16 and Table 2, the landcover in River Oaks Park is split
between forest, woodland, savanna, and bluff prairie. Most are dry or dry -mesic
communities, due to the sandy soils and southern exposures. Aspect determines the
difference between similar soil areas, since those aspects that face more south and
west, are drier than those that face north and east. Depth to bedrock is another
factor that determines plant community, since shallow soils that are close to
Friends of the Mississippi River 40 River Oaks Park NRMP
N
d
L
MLCCS Unit
V
Q
Dominant Soil Type(s)
Aspect
Target Community
Sparta Loamy sand, 6 -15%
Relatively
Southern Dry -Mesic Hardwood
Oak Forest -1
0.21
slopes (8C)
Flat
Forest (MHs37)
Oak Woodland-
Sparta Loamy sand, 2 -6%
Relatively
Southern Dry -Mesic Woodland
Brushland
0.59
slopes 8B
Flat
FDs37
Sparta Loamy sand, 6 -15%
Oak Woodland-
slopes (8C) and Mahtomedi
Brushland, Oak
Variant- -Rock Outcrop
Forest -2, Alt/NN
Complex, 25 -60% slopes
South-
Southern Dry Savanna
Mixed Wood
0.78
(1820F)
southeast
(UPs14)
Sparta Loamy sand, 6 -15%
slopes (8C) and Mahtomedi
Dry prairie
Variant - -Rock Outcrop
bedrock bluff
Complex, 25 -60% slopes
South-
Southern Dry Bedrock Bluff
subtype
0.49
(1820F )
southwest
Prairie (UPs13)
Mahtomedi Variant - -Rock
Outcrop Complex, 25 -60%
South-
Southern Dry -Mesic Woodland
Oak Forest -2
0.04
slopes (1820F)
southeast
(FDs37)
TOTAL 2.11
As can be seen from Figure 16 and Table 2, the landcover in River Oaks Park is split
between forest, woodland, savanna, and bluff prairie. Most are dry or dry -mesic
communities, due to the sandy soils and southern exposures. Aspect determines the
difference between similar soil areas, since those aspects that face more south and
west, are drier than those that face north and east. Depth to bedrock is another
factor that determines plant community, since shallow soils that are close to
Friends of the Mississippi River 40 River Oaks Park NRMP
bedrock cannot provide as much rooting areas as deeper soils, and tend to be drier,
and thus more prairie -like.
Restoration Process
Restoration is a process. It takes time to restore ecosystems to their former
functionality and diversity. Sometimes this can only be approximated. It took many
years to degrade the ecosystem and biological communities River Oaks site, so it will
not be restored overnight. Many steps are typically involved in a successful
restoration. Even deciding when a restoration is complete /successful can be very
difficult. Restoration should be viewed as a process not a state of being. The
ultimate goal is to achieve and maintain a diverse natural community at the site. A
good guide on how to conduct restoration is using the concept of adaptive
management. Adaptive management is a strategy commonly used by land managers
and restorationists, and integrates thought and action in the process. It can be
described as a strategy that uses evaluation, reflection, communication, and also
incorporates learning into planning and management. It is set up like a feedback
loop and looks like this: Assess Problem -4 Design -4 Implement -4 Monitor -4
Evaluate -4 Adjust -4 Assess Problem -4 and so forth. Thus, moving forward with
restoration, each round of adaptive management refines and hones the process to
better fit the conditions of the site and time. This strategy should be used at River
Oaks Park.
Given the narrowness of the parcel, it will take more effort to maintain this site than
if it were a larger parcel. This is a small, narrow property that has a lot of "edge"
and thus more possibilities for invading species. As stated earlier, engaging
neighbors in this restoration effort will not only help the specific restoration on the
park be more successful, because it will reduce the potential seed source of exotic
invasive plants, but will also increase the size of natural communities being
managed in the area generally.
The restoration of the biological communities at River Oaks Park property will be
broken into phases. Each phase will address the restoration of each given target
plant community. Phases will be spread out over a number of years. Restoration
will also be prioritized, with the most important resources or vital areas taking
precedence. On this site, the Bluff Prairie is the highest priority because this plant
community is vulnerable to extirpation in the state of Minnesota, and is quite rare in
Washington County (personal communication with staff at Washington
Conservation District, January, 2012) and thus will be given preference in this plan.
The second priority is restoring the Mesic Savanna unit, since savanna is also a
vulnerable plant community. The third priority is restoring the areas of forest
and /or woodland on the property.
Table 4 is a schedule of proposed management activities and cost estimates, and
lists each step in the process.
Friends of the Mississippi River 41 River Oaks Park NRMP
Site -Wide Invasive Woody Plant Removal /Control
The initial restoration goal will be the eradication of non - native woody species.
Because of the small size of the property, this should be done all at the same time.
The entire restoration process typically takes three to five years. Note that closely
integrating seeding, following removal, may be necessary, especially on the steep
slopes that constitute the greater part of this property. Part of the exotic woody
control would be prescribed burns, which will reduce seedlings of exotic species and
will help to foster native species.
Restoration Priorities
PRIORITY 1: Restore /Protect Bedrock Bluff Prairie
Woody Plant Removal
Since this is such a small area, the bluff prairie should be entirely cleared of exotic,
invasive brush. Then the site should be assessed for further woody removal,
including native species. Almost all of the woody material on the bluff prairie
should be either removed or set back. Primary species to remove are common
buckthorn, Tartarian honeysuckle, redcedar, basswood, hackberry, with some Amur
maple, and Siberian elm also. A few bur oaks can remain, which would not be out of
accord with the native community, but that's about it for woody plants. Cut stumps
should be treated with Glyphosate (via hand -held spray bottles because they are
easy to handle on steep slopes). This should be applied to stumps on a calm day
during the growing season when temperatures are above freezing but not above 85
degrees. If not treated, stumps will sprout with multiple stems, thus creating a
difficult situation to control, since even more cutting and herbicide will be required
on the multiple resprouts. Use of chemicals should be done with extreme care on
this site, especially on the bluff prairie, given the high potential for groundwater
contamination and the high diversity of native prairie plants. It is recommended to
use Glyphosate. Glyphosate binds to soil particles and is generally not mobile, so it
is a better choice than other herbicides that are more mobile.
Working on steep slopes presents a challenge on this property. Hand cutting of all
woody brush is recommended for these steep, sensitive slopes. Operating
equipment here would be very dangerous. Footing will be treacherous so proceed
with caution keeping safety the highest priority. Using trained professionals (city
staff or contractors) on the bluff prairie would be recommended. Volunteers can be
utilized for areas that are not too steep. Costs for working on the steep slopes will
undoubtedly be higher than the flatter areas. Brush near the ridge top can be
hauled up top. Brush farther down the slope will be easier to haul down to the
bottom, being careful to keep it well away from the rail tracks. Brush pile locations
will need to be determined, considering access and proximity to the road. Burning
of brush piles will probably not be an option close to the highway. Details will have
to be worked out in the field at the time of removal.
Friends of the Mississippi River 42 River Oaks Park NRMP
Shrub Control
Non - aggressive native shrubs, such as leadplant, should stay. Aggressive native
shrubs such as prickly ash and smooth sumac should be controlled. Prickly ash, a
native shrub of open woodlands and savannas, can be controlled in areas that it is
overabundant in the bluff prairie. Cutting and treating of stumps is recommended
to control overabundant populations, but eradication is not recommended. Burning
will top -kill prickly ash, but will not kill the root.
Smooth brome can also be mechanically treated, but need not be eradicated. The
small size of the site, though, may dictate that it gets virtually eradicated. Repeated
burning will keep populations in check (Appendix C).
If adjoining landowners are engaged to manage their sites in conjunction with the
City Park bluff prairie, then efforts should be made to coordinate the management
activities of the various sites together. For instance, smooth sumac control should
be done at the same time so as to get a consistent and efficient treatment.
Grass Control, Burning and Seeding
There is only a small patch of smooth brome (Bromus inermis) at the top of the bluff
prairie, and this should be eradicated. Eliminating smooth brome on the steep bluff
prairie slopes involves properly timed activities. First attempts should be late
season burns. Late season burns are beneficial because they more completely
deplete plants of energy reserves by destroying the biomass of the topgrowth. Early
season burns will only destroy what little topgrowth has formed at that early part of
the growing season. Late season burns also are more damaging to native forbs, so it
is recommended to switch to early season burns in successive years, once smooth
brome has been controlled. A late - season burn should be adequate. Then switch to
a regular burning cycle of 2 to 5 years. If late - season burning alone proves to be
unsuccessful, then spot treatments of herbicide can be performed. Also, spot
burning (using a blow torch) could be done. Care should be taken to reduce
collateral damage to the native plants (Appendix Q.
Dry prairies do not require as frequent burning as do mesic ones, since tree and
shrub invasion is somewhat inhibited by dry and nutrient poor conditions of the soil
(MN DNR, 2005). However, as can be seen from the dense vegetation of this site,
they still do require frequent enough fire to keep woody plants from invading. A
late season burn is recommended for the bluff prairie, followed by burns every 3 to
5 years from then on. This site is really too small to divide into burn units, which is
the typical recommendation for prairie sites. If adjoining landowners are engaged to
restore their portions of the bluff prairie, then their parcels should be included in
the burn plan. If there are disjunct properties, then division into burn units may
make good sense. The site should be evaluated after each burn to see how well
plants (and animals) recover.
Friends of the Mississippi River 43 River Oaks Park NRMP
Seeding should not be necessary for the majority of the bluff prairie, since there
already exists an adequate native species cover on the unit. At the edges and new
areas that are being created, pushed out into the adjacent woodland units, seeding
will be needed. It is recommended to collect seed from on site and then use that
seed to restore buffer areas of the prairie. Evaluate over the first couple of years of
restoration, and if seeding method is not working, or if additional seed is required,
then purchase local ecotype seed (within 100 miles) from a reliable vendor
(Appendices B and E) and broadcast this seed following a burn.
PRIORITY 2: Restore Oak Savanna
The Oak Savanna unit will require tree and shrub (brush) removal. Brush removal
can be accomplished in a similar fashion as on the Bluff Prairie, in terms of
treatment of stumps. Large bur oaks should be left in this unit, but most of the other
trees should be removed.
Woody debris should be gathered and stacked into burn piles, which can be located
scattered throughout the property. Protect trees from heat damage by locating piles
in forest openings at suitable distances from trees. Piles are best burned in winter
when a light snow cover exists (e.g. 3 -6 inches); otherwise fall is acceptable, too.
Since this is such a small site and it is a city park, stem scattering is not
recommended.
Where there are oak wilt infections occurring, it is recommended to let them go
without treating, as long as the fungus stays in the pin oaks. Oak wilt is acting to
open up the site naturally. Monitor the oak wilt disease, however, and if the
infection spreads to bur oaks, then suppression of the disease is warranted. (If the
city's property is the core infection area, they may need to consider taking action so
the infection does not spread to neighboring private lands).
Since this site is fairly degraded, seed will most likely have to be purchased. Try
collecting as much as possible, but purchase of local ecotype seed is appropriate
here. Erosion control blanket will be necessary on the southeastern part of this unit,
due to the steeper terrain here.
Burn the savanna unit in similarly to the bluff prairie: more often at first, and then
on a rotation of about every 3 to 5 years. If burning is not part of the management,
this unit will rapidly succeed to forest, since there are many pin oak seedlings and
buckthorn seedlings on the ground. The savanna unit may be burned in conjunction
with the bluff prairie for most years, but juxtaposing it against the bluff prairie burn
cycle is recommended for some of the burns.
PRIORITY 3: Restore Dry -Mesic Oak Forests and Dry -Mesic Oak Woodlands
The Dry Mesic Woodlands and Dry -Mesic Forests are more degraded than the bluff
prairie and will require more effort to restore. This coupled with the fact that the
woodland and forest units are relatively long and narrow, with lots of edge, makes
these units a lower priority for restoration.
Friends of the Mississippi River 44 River Oaks Park NRMP
As with the Savanna unit, restoration will involve woody brush removal, followed by
burning. Restoration of the ground layer will be more difficult due to the reduced
amount of light that reaches the ground, as compared to a more open landscape.
Buckthorn is large and dense in the woodland units, and thus controlling it will
require cutting and stump treating with herbicide (Appendix Q. Again, as in the
Savanna units, woody debris should be gathered and stacked into burn piles, which
can be located scattered throughout the property. Protect trees from heat damage
by locating piles in forest openings at suitable distances from trees. Piles are best
burned in winter when a light snow cover exists (e.g. 3 -6 inches); otherwise fall is
acceptable, too.
For restoration of the ground layer, seed will have to be purchased for the forests
and woodlands (Appendix B is a species list). Forest seed is notoriously slow to
germinate, so perhaps it would be best to plant plugs (small transplants) in plots to
add diversity to the forest. Because of high deer populations, it may be necessary to
protect plantings with fencing surrounding each plot. Seed tends to germinate more
readily in woodlands, since they are more open to light. Taking advantage of canopy
gaps is recommended for seeding.
Planting of shrubs to add diversity is also recommended (Appendix B). Trees do
not need to be planted, although planting oaks may be necessary for regeneration of
oaks in the forest and woodlands. Oaks require light for growth, so planting in gaps
is recommended. Protecting each shrub or oak tree with a wire cage is
recommended. Watering during dry spells is also recommended the first year after
planting, but logistics on watering in this park will be tricky. It would be best to
plant in spring to take advantage of early season soil moisture. Remember to
protect shrub plantings from fire for five years, and new seedlings for two to three
years, lest they be killed before they become established.
Prescribed Burns —More Information
Although it is usually recommended to split the entire site up into burn units, for
ease of operation and for ecological reasons (impacts on insects and animals, for
instance), the small size of this site may not allow this. However, it is important to
leave some areas unburned (refugia) to allow insect and animal populations to
recover and repopulate burned areas. In this case if burning only takes place on the
city's property, the privately owned prairie would provide the refugia. If burn units
are utilized, rotate the burning of the units from year to year, and try not to burn
adjacent units in consecutive years. Prior to a prescribed burn, a burn plan must be
devised. The burn contractor can help with the burn plan. Permits must be
obtained from the DNR and local fire officials. Initially, burning would be rotated
every one or two years, so that each year a different burn unit would be burned.
Long -term, burns should occur every 5 -9 years in woodlands and 3 -5 years in
prairies and savannas.
Friends of the Mississippi River 45 River Oaks Park NRMP
Prior to burning, burn breaks must be created to contain the fire. Burn breaks
consist of a mowed swath in grassland areas, typically at least 8 feet wide. In
woodland areas, the break line is created by clearing the leaf litter and any other
debris to reach mineral soils. Locating breaks on the periphery of the parcel is a
logical place for them. The burn contractor can also help with the placement and
installation of burn breaks. Allowing fire to run into adjacent different land covers is
a good strategy. For example, breaklines in a prairie unit that is adjacent to
woodland should be placed a short distance into the woodland, where feasible. This
makes for a more natural looking and functioning landscape and helps to prevent
the woodland from encroaching into the prairie.
Smoke management is the main concern for burning on this property, since there are
a number of nearby residences, buildings, and roads. Take into consideration the
direction and amount of smoke that will come from burning of this property, and
plan accordingly. Notification of nearby neighbors is highly recommended.
Long -Term Monitoring and Maintenance
Monitoring is very important to restoration success. Monitoring, evaluation and
assessment should be done at least annually by an ecologist or a restoration
professional. More frequent monitoring will be needed in the initial phases of
restoration to evaluate the success of the methodology and to inform future
strategies. Adapting to issues or factors observed during monitoring and
assessment is vital to the restoration process.
Once the primary restoration tasks are completed, the restoration process will
convert to a monitoring and adaptive management phase. Long -term maintenance
for the woodland areas will consist of burning every 5 to 9 years and monitoring
every year and managing for exotic species. Dry -Mesic Oak Forests (those that are
very dense and occur on moist soils and north to east - facing slopes) and Lowland
Hardwood Forests will require burning once every 20 years. For Prairies, burning
should occur every 3 to 5 years.
Restored areas must be regularly monitored to identify ecological issues, such as
erosion and sedimentation, invasive species, and disease. Monitoring is also
important for detecting human - related issues such as illegal activities (hunting, ATV
use, tree harvesting, etc.) Early detection of concerns enables quick responses to
address them before they become significant problems.
Involving the neighbors in restoration activities will be very important. Possible
ways to get neighbors involved may be to offer a volunteer event that would be an
educational tour about the ecology of prairie and savanna and history of the site.
Friends of the Mississippi River 46 River Oaks Park NRMP
RESTORATION SCHEDULE AND COST ESTIMATES
An approximation of restoration /management tasks, priorities, and costs are
provided in Table 3, below. Project cost estimates are not based on actual
contractor bids, but on typical costs for similar projects. Actual project costs could
be significantly higher or lower, depending on multiple factors. Costs could
potentially be decreased by, for example, reducing the diversity of prairie seed costs,
contracting for the entire project with one contractor, using volunteers or STS
(Sentence to Serve) crew for portions of the labor such as hauling brush. Some
activities may be carried out by the landowner if they wish, and have the time and
equipment to do so. Project tasks and costs may also change over time, as more
information is learned about the property and as the site conditions change.
The most important short -term issue to address is exotic woody species control at
all the units. Ideally, this should be addressed site -wide prior to any other
restoration activities to eliminate seed sources of these exotic species. However, if
budget concerns preclude this, woody brush removal may be phased and
accomplished over several years time.
Table 3. River Oaks Park Restoration Schedule and Cost Estimates
These tables are rough schedules and approximate costs for restoration and management
tasks for the River Oaks Park property. Both the project tasks and costs are likely to change
as the project progresses - these tables should be used only as rough guides. Tasks were
phased, with 1 being the highest priority. Work units correspond with those shown in
Figure 15.
Friends of the Mississippi River 47 River Oaks Park NRMP
Cost
Year
Season
Units
Activity
Acres
Cost /Ac
Est.
Control large exotic woody
brush plants and other
Fall,
undesirable native woody
winter,
ALL
brush. Haul brush to piles
1 &
early
UNITS
and either remove or burn
2
spring
in winter.
2.1
$1
$3,150
Control non - native grasses
Fall (1st
(smooth brome, Kentucky
or 2nd
bluegrass, reed canary
1 &
wk of
UPs13,
grass). Broadcast -apply
2
October
UPs14
herbicide in fall.
1.3
$200
$260
Conduct prescribed burn on
Spring
bluff prairie, and if possible
(Mar,
UPs13,
into nearby oak savanna
Apr,
UPs14,
unit, and oak woodland
2
Ma
FDs37
unit.
1.9
$300
$570
Seed parts of savanna,
UPs14,
woodland, and forest with
FDs37,
native cover crop seed
2
June
MHs37
following burn.
1.6
$600
$960
Friends of the Mississippi River 47 River Oaks Park NRMP
Friends of the Mississippi River 48 River Oaks Park NRMP
Engage neighboring
landowners who share
1 &
ownership of the bedrock
$1,500
2
Any
bluff prairie.
MHs37,
FDs37,
Summer,
UPs -14,
2
fall
UPs13
Treat exotic res routs.
2.1
$150
$315
MHs37,
FDs37,
Summer,
UPs -14,
Spot treat herbaceous
2
fall
UPs13
weeds and exotic grasses.
2.1
$100
$210
Summer,
2
fall
UPs13
Collect seed on bluff prairie.
0.5
$100
$50
MHs37,
FDs37,
UPs -14,
Annual Ecological
2
Any
UPs13
evaluation and assessment.
2.1
$350
$735
Conduct second prescribed
Spring
burn on bluff prairie and, if
(Mar,
UPs13,
possible into nearby oak
Apr,
UPs14,
savanna unit, oak woodland
3
Ma
FDs37
unit.
1.9
$250
$475
Seed savanna, woodland,
and forest with diverse
local ecotype seed mixes, if
UPs14,
necessary. Plant shrubs at
May,
FDs37,
a low density. Plant
3
June
MHs37
herbaceous plugs in plots.
1.6
$1,000
$1,600
3
Any
Re- evaluate after burn.
$300
$4,845,
per 3
TOTAL
yrs
$10,175
Friends of the Mississippi River 48 River Oaks Park NRMP
Long -Term Management
Once initial restoration tasks are completed, then long -term management ensues.
Long -term management includes tasks that are required to be done periodically to
maintain the plant community. Table 4 lists these tasks with associated cost
estimates.
Table 4. River Oaks Park Long -Term Management Schedule and Cost
Estimates
TOTAL $1,276 $2,680
Friends of the Mississippi River 49 River Oaks Park NRMP
Cost
Year
Season
Units
Activity
Acres
Cost /Ac
Est.
4
thru
Spring or
UPs13,
Burn the Bluff Prairie and
10
fall
UPs14
Savanna ever 2 -5 years.
1.3
$300
$1,170
4
F a l l
thru
and /or
Burn the oak woodland
10
spring
FDs37
units ever 7 -9 years.
0.6
$300
$180
4
Fall,
thru
summer,
Evaluation and assessment
10
spring
All
by ecologist
2.1
$1,030
4
thru
Summer,
Monitor for oak tree
10
winter
All
disease.
2.1
$300
TOTAL $1,276 $2,680
Friends of the Mississippi River 49 River Oaks Park NRMP
WORKPLAN
The following tasks and budget (Table 5) are based on known costs and project
needs at the time of the restoration agreement. All parties, prior to implementation,
will agree upon additional future tasks. Work units are shown on Map in Figure 15.
Table 5.
4
th ru
10 Long -term Management 2.1 $3,900
1
thru TOTAL Initial restoration plus
10 long-term management $16,500
Friends of the Mississippi River 50 River Oaks Park NRMP
N
i
W
J
M
L
v
Q
o
rte' r OL
V v O
r
O
Yr
Activity
v
Breeding bird surveys
0,1,
June
and ecological
2,3
evaluations.
2.1
$3,400
Fall,
Control large exotic
winter,
woody brush plants and
early
other undesirable native
1
spring.
woody brush.
2.1
$3,200
Control non - native
Summer
grasses (smooth brome,
Fall
Kentucky bluegrass,
1,2
reed canary grass).
1.5
$300
Any
Engage neighbors with
1,2
bluff prairie.
$1,500
Spring,
Conduct prescribed
2,3
Fall
burns
1.9
$1,000
Summer
Follow up control of
, fall
exotic brush (resprouts)
2,3
and herbaceous weeds.
2.1
$500
Summer
Seed collection on bluff
2
Fall
prairie.
0.5
$100
Broadcast seeding of
Spring,
native prairie seeds,
Fall
planting of native
herbaceous plugs, and
2, 3
planting of native shrubs.
1.6
$2,600
SUBTOTAL
$12,600
4
th ru
10 Long -term Management 2.1 $3,900
1
thru TOTAL Initial restoration plus
10 long-term management $16,500
Friends of the Mississippi River 50 River Oaks Park NRMP
Information Sources
. 1977. Soil Survey of Washington and Ramsey Counties Minnesota. Soil Conservation
Service. United States Department of Agriculture, in cooperation with the Minnesota
Agricultural Experiment Station.
1998. Natural Resources Inventory: Final Report. Bonestroo, Rosene, Anderlik, &
Associates.
. 2001. Minnesota Land Cover Classification System. MNDNR St. Paul, MN.
.2005. Field Guide to the Native Plant Communities of Minnesota: The Eastern
Broadleaf Forest Province. Ecological Land Classification Program, Minnesota County
Biological Survey, and Natural Heritage and Nongame Research Program. MNDNR St.
Paul, MN.
. 2006. Tomorrow's Habitat for the Wild and Rare: An Action Plan for Minnesota Wildlife,
Comprehensive Wildlife Conservation Strategy. Division of Ecological Services, Minnesota
Department of Natural Resources. St Paul Baldwin Plains:
http: / /files.dnr.state.mn.us/ assistance /nrplanning /bigpicture /cwcs /profiles /st_paul_bald
win_plains.pdf
Foth, Henry D (Michigan State University). 1990 (8th Edition). Fundamentals of Soil
Science. John Wiley & Sons, New York, New York.
Frelich, Lee E., and Andrew Holdsworth. 2002. Exotic Earthworms in Minnesota
Hardwood Forests: an investigation of earthworm distribution, understory plant communities,
and forestfloor dynamics in northern hardwood forests. Department of Forest Resources,
University of Minnesota, 1S30 Cleveland Ave. N., Saint Paul, MN SS108
Marschner, F.J., 1974. The Original Vegetation of Minnesota. Map compiled from U.S.
General Land Office survey notes. U.S. Forest Service, North Central Forest Experiment
Station, St. Paul.
Meyer, Gary N., R. W. Baker, C. J. Patterson. 1990. Surficial Geology in: Geologic Atlas
Washington County, Minnesota. University of Minnesota, St. Paul.
Minnesota Department of Natural Resources. 1997. Natural communities and rare
species of Dakota County. Minnesota County Biological Survey Map Series No. 1.
Mossler, J.H. 1990. Bedrock Geology in: Geologic Atlas Dakota County, Minnesota.
University of Minnesota, St. Paul.
Swanson, Lynn and Gary Meyer, eds. 1990. Geologic Atlas Washington County,
Minnesota. Minnesota Geologic Survey. University of Minnesota, St. Paul.
Friends of the Mississippi River 1 River Oaks Park NRMP
Websites:
Exotic species control methods: http: / /dnr.wi.gov /invasives /index.htm
Great Britain Forestry Commission: http:// www .forestry.gov.uk /fr /INFD- 678DWY
MN Natural Resources (DNR): http:// www .dnr.state.mn.us /nr /index.html
Natural history of MN, bibliography (DNR):
http: / /www.dnr. state. mn. us / snas /naturalhistory_resources.html
Earthworm website: http:/ /www.nrri.umn.edu /worms/
Forest Ecology:
http/lcffe.cfans.umn.edu /
Bur Oak Blight
http / /www.myminnesotawoods.umn.edu /2010 /09/ bur - oak - blight- bob- in- minnesota/
Oak Wilt
http/ /www.dnr.state.mn.us /treecare /forest health /oakwilt /index.html
Important Bird Area, Audubon Society
http:// iba. audubon .org/iba/profileReport.do ?siteld= 2421 &navSite = search &pagerOffset =0
&page =l
Friends of the Mississippi River 2 River Oaks Park NRMP
APPENDIX A Plant Species Recorded at the River Oaks Park Property
The following plant species were identified at the site by Friends of the Mississippi
River in 2012.
Bedrock Bluff Prairie, Southern
a,
E s
T Z Z ' Scientific Name Common Name Cover a v Comments
CANOPY /SUBCANOPY 12 to 70 ft height Total Cover: 1 to 2
GROUND LAYER to 4 ft height Total Cover: 3 to 4
Graminoids
Acer negundo
Boxelder
+
Celtis occidentalis
Hackberry
1
3 to 10
Invading into prairie
Juniperus virginiana
Eastern redcedar
3
2 to 6
Invading into prairie
x
Prunus serotina
Black cherry
+
2 to 4
One significant patch;
otherwise not common.
Quercus macrocarpa
Bur oak
+
3 to 10
Tilia americana
American basswood
2
2 to 4
Invading into prairie
Ulmus americana
American elm
1
2 to 4
x
Ulmus pumila
Siberian elm
2
2 to 4
Invading into prairie
Schizachyrium scoparium
Little bluestem
1
UNDERSTORY /SHRUB LAYER 4 to 12 ft height
1
:Total Cover: 2 to 3
Indian grass
Amorpha canescens
Lead plant
+
Sporobolus heterolepis
Prairie dropseed
Celastrus scandens
American Bittersweet
1
Stipa spartea
Needle grass
Celtis occidentalis
Hackberry
1
Juniperus virginiana
Eastern redcedar
2
Invading into prairie
•
Lonicera tatarica
Tartarian honeysuckle
2
Invading into prairie
Quercus ellipsoidalis
Northern pin oak
+
Quercus macrocarpa
Bur oak
1
•
Rhamnus cathartica
Common buckthorn
3
Dominant in many parts
Rhus glabra
Smooth sumac
3
Invading into prairie
Rubus spp.
Recumbant blackberry
+
One patch on west end
Tilia americana
American basswood
2
Invading into prairie
Zanthoxylum
americanum
Prickly ash
2
Invading into prairie
GROUND LAYER to 4 ft height Total Cover: 3 to 4
Graminoids
Friends of the Mississippi River 1 River Oaks Park NRMP
Andropogon gerardii
Big bluestem
+
Boutelua curtipendula
Side oats grama
2
Boutelua hirsuta
Hairy grama
1
x
Bromus intermis
Smooth brome
+ to 1
One significant patch;
otherwise not common.
Carex schweinitzii
Schweinitz's sedge
+
Dicanthelium
oligosanthes
Panic grass, cf.
Scribner's
+
Elymus virginicus
Wild rye
+
Muhlenbergia cuspidata
Muhly grass
1
Schizachyrium scoparium
Little bluestem
1
Sorghastrum nutans
Indian grass
+
Sporobolus heterolepis
Prairie dropseed
1
Stipa spartea
Needle grass
1
Friends of the Mississippi River 1 River Oaks Park NRMP
Bedrock Bluff Prairie (cont'd.)
Forbs
Ambrosia artemisiifolia
Common ragweed
1
Amorpha canescens
Leadplant
+
Anemone cf. cylindrica
Thimbleweed
+
Antennaria plantaginifolia
Plantain - leaved
pusse toes
+
Aquilegia canadensis
Columbine
1
Ascleplas tuberosa
Butterflyweed
1
Aster ericoides
Heath aster
+
Aster oolentangiensis
Sky blue aster
1
Aster sericeus
Silky aster
2
Cal to hus serrulatus
Yellow sun drops
+
Celastrus scandens
American bittersweet
1
Chenopodium spp.
Lambs ear -like plant
+
Comandra umbellata
Bastard toadflax
1
Dalea pur urea
Purple prairie clover
1
Erigeron spp.
Daisy fleabane species
+
Euphorbla corollata
Flowerings urge
1
Hellanthus cf. pauciflorus
Sunflower cf. naked
1
Heliopsis hellanthoides
Early sunflower
1
Juniperus virginiana
Redcedar
1
Seedlings
Latuca canadensis
Wild lettuce
+
Liatris punctata
Dotted blazing star
1
Monarda flstulosa
Bergamot
+
Oenothera blennis
Evening primrose
1
Physalls heterophylla
Clammy ground cherry
1
Potentilla arguta
Prairie cinquefoil
+
Pulsatilla patens
Pasque flower
+
Quercus ellipsiodalis
Pin oak
+
iSeedlings
Quercus macrocar a
Bur oak
+
Seedlings
x
Rhamnus cathartica
Common buckthorn
1
Seedlings
Rhus glabra
Smooth sumac
1
Shoots
Rudbeckia hirta
Black -eyed Susan
1
Solidago canadensis
Canada goldenrod
1
Solidago nemoralis
Grey goldenrod
+
Toxicodendron rydbergii
Poison ivy
1
x
Tragopogon cf. dubious
Goat's beard
+
Triosteum perfoliatum
Late horse gentian,
feverwort
+
Verbena stricta
Hoary vervain
2
Violet spp.
Violet species
+
Vines
Vitis ri aria
Grape vine
+
Celastrus scandens jAmerican
Bittersweet 1
2
Friends of the Mississippi River 2 River Oaks Park NRMP
Woodland, Dry -Mesic Oak
>_-
C
Z Z ' Scientific Name
Xommon Name
L
E.c!
U
Cover p ( Comments
CANOPY
_
20 -80 ft height
- Random spacing: 10, 1.
jTotal Cover: 2 to 3 i30, 50 ft
Acer ne undo
Boxelder
1
6 to 15
Celtis occidentalls
Hackberry
1
6 to 15
Juniperus virginiana
Redcedar
2
4 to 10
Common
Populus deltoides
Eastern cottonwood
+
20 to 45
Populus tremuloides
Quaking aspen
2
5 to 10
Patchy.
Prunus serotina
Black cherry
2
6 to 15
Dominant in parts
Quercus macrocarpa
Bur oak
2
6 to 18
Co- dominant
Quercus ellipsoidalls
Northern pin oak
2
6 to 15
Co- dominant
Tilia americana
American basswood
1 to 2
6 to 12
Multistems common
Ulmus americana
American elm
1
6 to 12
x
1 Ulmus pumila
I Siberian elm
I + to 1
1 6 to 12
SUSCANOPY
12 to 20 ft height
Total Cover: 2 to 3
Acer negundo
Boxelder
1 to 2
Celtis occidentalis
Hackberry
2
Juniperus virginiana
Redcedar
+ to 1
Populus deltoides
Eastern cottonwood
+
Populus tremuloides
Quaking aspen
1
Patchy
Prunus serotina
Black cherry
2
Quercus macrocarpa
Bur oak
1
Quercus Oil psoidalis
Northern Pin oak
2
Dominant
Tilia americana
American basswood
1 to 2
Ulmus americana
American elm
1
x
1 Ulmus pumila i
Siberian elm I
+ to 1
UNDERSTORY /SHRUB LAYER 4 to 12 ft height
Total Cover: 4 to 5
Corpus racemosa
Grey dogwood
1
Patchy
x
Lonicera tatarica
Tartarian honeysuckle
1 to 2
Co- dominant with BT
and Prickly Ash.
Prunus serotina
Black cherry
1
Prunus virginiana
Choke cherry
1
x
Rhamnus cathartica
Common Buckthorn
3
Dominant
Rhus glabra
Smooth sumac
1
Patchy
Ribes cynosbati
Gooseberry
1 to 2
Rubus ideaus cmplx.
Black raspberry
1
Zanthoxylum americanum
Prickly ash
2 to 3
Co- dominant with BT
and HS.
Friends of the Mississippi River 3 River Oaks Park NRMP
Woodland, Dry -Mesic Oak (cont'd.)
GROUND LAYER
Graminoids
to 4 ft height
(Total Cover: 3 to 4
-
Carex pensylvanica
Pennsylvania sedge
1
•
Phalaris arundinacea
Reed canary grass
+
patchy
•
Poa pratensis
Kentucky bluegrass
1
Forbs
•
Actium minus
Burdock
+
•
lAntrhiscus sylvestris
Wild chervil
Carex radiata
Wood sedge
+
Celtis occidentalis
Hackberry
1
seedlings
•
Cirsium arvense
Canada thistle
+
Cirsium discolor
Field thistle
+
•
Cirsium vulgare
Bull thistle
1
•
Hesperis matronalis
Dame's rocket
1
Eupatorium rugosum
White snake root
2
•
Leonurus cardlaca
Motherwort
1
•
Lonicera tatarica
Tartarian honeysuckle
1 to 2
seedlings
•
Nepeta cataria
Catnip
1
Polygonatum pubescens
Solomon's seal
+
Prunus serotina
Black cherry
1
seedlings
Quercus ellipsiodalis
Pin oak
2
Seedlings abundant.
Quercus macrocarpa
Bur oak
+
seedlings
•
Rhamnus cathartica
Common buckthorn
3 to 4
seedlings
Rubus cf. ideaus
Red raspberry
1
Sanicula marilandica
Black snake root
1
Solidago canadensis
Canada goldenrod
1 to 2
•
Sonchus arvensis
Perennial sow thistle
1
Thalictrum thalictroides
Rue anemone
+
Vines
Vitis ri aria
Grape vine
1
Friends of the Mississippi River 4 River Oaks Park NRMP
Forest, Dry -Mesic Oak
C },
i Z ! Scientific Name
Common Name
V
Cover p
,Comments
CANOPY
20 -80 ft height
Total Cover: 2 to 3
.'
Acer negundo
Boxelder
1
Celtis occidentalis
Hackberry
2
8 to 25
Fraxinus pennsylvanica
Green ash
1 to 2
10 to 35
Juglans cinerea
Butternut
+
6 to 10
Afflicted with canker.
Juglans nigra
Black walnut
+
6 to 20
Prunus serotina
Black Cherry
1
8 to 20
Quercus macrocarpa
Bur oak
1
20 to 40
Quercus ellipsoidaHs
Northern pin oak
1
8 to 25
Tilia americana
Basswood, American
2
8 to 30
Ulmus americana
American elm
1 to 2
8 to 14
SUSCANOPY
;12 to 20 ft height
Total Cover: 3 to 4
Acer negundo
Boxelder
1
Celtis occidentalis
Hackberry
2
Fraxinus pennsylvanica
Green ash
2
Prunus serotina
Black cherry
2
Quercus macrocarpa
Bur oak
1 to 2
Quercus rubra
Red oak
2
Tilia americana
Basswood, American
2
Ulmus americana
j American elm
1 to 2
s }
UNDERSTORY /SHRUB LAYER 4 to 12 ft height
Total Cover: 2 to 3
•
Lonicera tatarica
Tartarian honeysuckle
1
Prunus virginiana
Choke cherry
1
•
Rhamnus cathartica
Common buckthorn
2 to 3
Dominant
Ribes cynosbad
Gooseberry
1
Sambucus pubens
Red berried elder
1
I
GROUND LAYER
Graminoids
to 4 ft height
Total Cover:
3
Carex blandii
Bland sedge
1
Carex pensylvanica
Pennsylvania sedge 1
2
Forbs and others
Actaea rubra
red baneberry
+
x
Actium minus
Burdock
1
Ambrosia artemisiifolia
Common ragweed
1
Eupatorium rugosum
White snakeroot
1
Galium a arine
cleavers
+
x 1
Leonurus cardiaca
Motherwort
1
Lonicera tatarica
Tartarian honeysuckle
1
x
Nepeta cataria
Catmint
+
Oryzopsis asperifolla
mountain rice grass
+
Osmorhiza claytonsi
clayton's sweet cicely
+
Parthenocissus
quinquefolia
virginia creeper
+
Prunus virginiana
chokecherry
1
seedlings
x
Rhamnus cathartica
Common buckthorn
2
Seedlings
Sanicula marilandica
Maryland black snake
root
+
Vids riparia
wild grape
1
Friends of the Mississippi River 5 River Oaks Park NRMP
Species List from Bonestroo Survey Report, 1998
Friends of the Mississippi River 6 River Oaks Park NRMP
APPENDIX B Plant Species for Restoration at River Oaks Park Property
Dry Bedrock Bluff Prairie (UPs13c)
Genus
Species
Common Name
Shrubs
cmx
canescens
White prairie-clover
-
Rosa
S mooth wil rose
Lead -plant
Amorpha
Forbs
c
Illinois tick - trefoil
Anemone
Long- headed
thimbleweed
Antennaria
spp.
Puss toes
A uilegia
canadensis
Columbine
Asclepias
verticillata
Whorled milkweed
Asclepias
tuberosa
Butterfly-weed
Asclepias
viridiflora
Green milkweed
Asclepias
s riaca
Common milkweed
Aster
ser iceus
Silk aster
Aster
Oolentan-
giensis
Sky -blue aster
Aster
ericoides
Heath aster
Aster
laevis
Smooth aster
As tragalus
Crassi-
carpus
Buffalo -bean
Calylophus
serrulata
Toothed evening
primrose
Campanula
rotundifolia
Harebell
Coreopsis
palmata
Stiff tickseed
Da /ea
j purourea
Purple prairie-clover
Da /e
candida
White prairie-clover
Delp hinium
carolini-
anum
Prairie larkspur
Desmodium
illinoense
Illinois tick - trefoil
Eu horbia
corollata
Flowering_ spurge
Gnap halium
Helianthem
Um j
Obtuse -
folium
S weet everlastin
bicknellii
Hoa ry frostweed
Helianthus
pauciflorus
Stiff sunflower
Heuchera
richardsonii
Alum -root
Hy ericum
perforatum
Common St. John's -
wort
Kuhnia
eupato-
roides
False boneset_
Round- headed bush -
clover
Lespedez
ca p it ata
Liatris !
aspera
Rough blazing star
Liatris j
punctata
Dotted blazing star
Liatris
cylindracea
Cylindric blazing star
Linum
sulcatum
Grooved yellow flax
Lobelia
spicata
Rouah- spiked Lobelia
Friends of the Mississippi River 1 River Oaks Park NRMP
Lysimachia
ciliata
Fringed loosestrife
Mirabilis
hirsuta
Hairy four- o'clock
Monarda
fistulosa
Wild bergamot
Oenothera
biennis
Common evening -
primrose
Oenothera
clelandii
Cleland's evening -
p rimrose
Oxalis
violacea
Violet wood - sorrel
Pediomelum
esculentum
Prairie- turnip
Pediomelum
argo h llum
Silvery scurf ea
Penstemon
grandiflorus
Large - flowered
beard-tongue
Physalis
virginiana
Ground-cher
Potentilla
arguta
Tall cinquefoil
Pycnan-
themum
virginianum
Virginia mountain -
mint
Scutella►ia
leonardi
Leonard's skullcap
Senecio
plattensis
Prairie ragwort
Silene
antirrhina
Sleepy catchfl
Field blue -eyed
Sisyrinchium campestre g rass
Solidago
nemoralis
Gray goldenrod
Solidago
rigida
Stiff goldenrod
Solidago
speciosa
Showy goldenrod
Tradescantia
occidentalis
spiderwo
iderwo
Viola
pedatifida
Prairie bird -foot
violet
Viola
pedata
Bird -foot violet
zizia
aptera
Heart- leaved
alexanders
Friends of the Mississippi River 1 River Oaks Park NRMP
Dry Bedrock Bluff Prairie (UPs13c)— cont'd.
Friends of the Mississippi River 2 River Oaks Park NRMP
Grasses,
Rushes and
Sedges
!
An dropogo n
( g erardii
Big bluestem
Bouteloua
_
curtipe _
_
j Side -oat grams _ _
Bouteloua
hirsuta
rama
C
1 l ongifolia
Sand reed - -
C arex
pensylvanica
Sunshine sedge
Cy peru s
schweinitzii
j Schweinitz' cyperus
Cyperus ___
Elymus
j _ lupulinus_ __j
wieg __ _t
H o -1p ike c ep rus - --
Canada wild rye _ _
_Eragrostis
Muhlenbe
f sp
' c uspidata
Purple love grass _
Plains mu hly
Panicum
oli gosanthes
Few - flowered panic
g rass
Panicum
wilcoxian
Wilcox's panic g ras s
Panicum
perlongum I
Long - leaved panic grass
Panicum -_
linearifolium
__._.
P nnear - l eaved panic
ass
P anicu m
leibe f
!*ber panic cra
S chizachy rium
wppa um
Little bluestem
Sor ghastru m
-
nutans F
Indian g rass T
Sporobolus 1
hete rolepis (
Prair dropseed
Sporob
asp er f
Rough dro pseed
Stipa spartea Porcupine -grass
Friends of the Mississippi River 2 River Oaks Park NRMP
Southern Dry -Mesic Oak Forest (MHs37)
Forbs
F orbs cont'd
Anemon
--
quinquefolia
Wood- anemone
Pyrola
- --
1 elliptica --
Co mmon pyrola
-
Anemone
A oc num
p y
virginiana I Tall thi
androsaemifo
lium Spreadin o
ban _ g
k 1_ P g d
Pyrola
Ranu
j secu
; abortivus
one -side pyrola
! Kidney -leaf buttercup
Ranunculu
I recurvatus
t' Hooked crowfoot
Aquilegia
Aralia -- -
cana densis
nudi caulcs
I Columbine
Wild sarsaparilla
Rubus
; pubes
( Dwarf ras pberry,
_
San guinaria ( canad
-
Bloodro
Aralia
Arenaria
j ra cemosa
lateriflor
r American spikena
f Side- flowering
sandw
-
Sani cula
E gregaria
t Gregarious black
C snakero
Sanicula
marclandica
Maryland black
snake root
Arisaema
triphylhim Jack -i th - pulp
Asclepias
exaltata
Poke milkweed
Smilax
I lasionuera
Carr flower
Aster
Aster
ciliolatus
lateriflorus
Lindl ey's aster
Side- flow ast
Solid
r Solidago
1 flexicaulis
j hispida
j Zig zag g oldenrod
Hairy go ldenrod
Aster
- -- - -
Aster
macrophy
Large l eaved aster
Solida
_o _
- Stre
uli inosa _
9
_ I _
; lanceolat J_ Rosytwisted-stal k
Bo g goldenrod
oldenrod
( Bo - -- -
_ 1
Oolentan
giensis Sky -blue aster
;
-- Thalictrum
das
Tall meadow rue -
- --
Aster
- --
sag ittifolius
-
Tail- leaved aster
- Thalictru
-
dioicum
- --
Ear l y - meadow -rue I
- - --- - - --
-- - --
Cau h llum
p y
thalictroides
= Blue cohosh
Thalictrum
thalictroides
Rue anemone
-- -
Circaea
- -
Clmtonia
Crypto taenia
-- - - -- - -
hite tiana
-
_ borealis
canadensis
Canada enchanter'
� nig
`- -
Bluebead lily -
I, Hone wort
-
Trien
- I
borealis
-
Starflower
--
- Trillium � cernuu 7
— - --
Nodding trillium
- Tr illium
-
_
I_ grandiflorum
Large - flowered
I_ tr illium
--
Desmodiu
- -
lutinosuin
-- - --
i Pointed - leaved
tick- trefoil
-
Uvularia
grandiflo
_
j Ye llow bellw
- U ular
sessilifolin
1 Pale bellwor
Diosco
villosa j Wild yam
Fra aria
9 - -
Fragarin
_ --
vesca
— -
virg miana
- -- -
Wo od st
-- --
Common strawb
Veroni
- castrum
} -- -
-
Viola
Zizia
I virginic
; species
aurea
Culve root
- - - -- -
Violet (multiple
species
; Golden alexanders
- t -
Galium 1
-
aparine Cleavers
-
Galium
boreale j Nor thern bedstra
G alium —
con cinnum
j Eleg ant bedstraw
- Grasses, Rushes and
Sedges
- g
-- - --
Galium
triflorum
-
Three - flowered
bedstraw
- -- -_ __
Brachy
-- el trum
-- ------- _�_-
erectum
.----- - - - - -- - --- _ - - - --
Beard shorthusk
Gerani
-
maculatuin L Wild geranium
- - - - --
Geum
- - - - --
cana dense
- --
White ayens
-
_y - -
Carex
- -- `
blan
-- - —
Char se '
g g
Geum
triflorum
j Prairie smoke
-- - _
Carex
--
= Ca rex
I deweyana C
I g racillima
_ _ ___ __..r
Dewey' sed ge
Grace sed
- - --
Helia
- - --
hirsutus Woodland sunflo
H elianthus
strumosus --
- - --
Rough -leaf sunflo
e Carex
p eckii 1
_
Peck's sedge
Hepatica ;
americana
--
k Round -lobed hepa
—
ii
- Ca rex
j p eduncula ta j
- - - -- - --
Long - s talked s edge
Heuchera f
ric
;Alum root
Carex
ens l y lvania
sedge f
L at hy ru s
Maianthemum (
venosus
ca
Veiny p
f Canada mayflower
Carex
ten
-
Marsh -str s
- --
- Carex
- -- . -``-
radiata
— - -- -
St ellate sedge
-- - -- -
Maianthemu
Mai
-- -
racemosum
stellatum
Racemose false
Solomon's -seal
Starry false
Solomon's -s eal
Elymus -
Festuca
-
hystrix !
subverticillata
- - -
Bottlebrush grass -
Nodding fescu
Oryzopsis
j asperifolia
Mou tain ric grass
--
Schizachne I
-
purpurascens (
- -
False melic grass
Mitchella
- - -- T - --
repens Partrid -berr
Osmorhiza
claytonii
-
; Clayton's sw eet ci
-
Ferns and Fer Allies
1 -
0smorhiza j
longistylis
i A nise -root
Athyr
Dr yopter is
filix femina
inte
Lad fern
Fancy wood fern
Phry _
leptostachy
Lopseed
Equisetcim
pratense
M ow horsetail
n --
Clammy ground
-
Matt
Osmunda
Pteridium
—
str
clay
' aquilinum 1
- --
F ost rich -f _
Interrupted fe rn
- - - - --
Bracken j
Friends of the Mississippi River 3 River Oaks Park NRMP
flowering stems bolt. It is applied at rate of 2 -4 lb /acre using a backpack or tractor -
mounted sprayer or in granular form. Dicamba could also be used, with the advantages
that it can be applied earlier in the spring at a rate of 1 lb /acre. Plants that do not respond
to treatment or that are more widely dispersed could be controlled mechanically.
Mechanical control, involving several cuttings per year for three or four years, can reduce
an infestation, if timed correctly. The best time to cut is when the plants are just beginning
to bud because food reserves are at their lowest. If plants are cut after flowers have
opened, the cut plants should be removed because the seed may be viable. Plants should be
cut at least three times throughout the season. Late spring burns can also discourage this
species, but early spring burns can encourage it. Burning may be more effective in an
established prairie, where competition from other species is good, than in an old field,
where vegetation may not be as dense.
Sweet clover
White and yellow sweet clover are very aggressive annual species that increase with fire.
Sweet clover should be eliminated by treatment in the same manner as smooth brome (see
below). Since it is a common plant in agricultural areas, if restoration is implemented, the
area should be surveyed for this species on an annual basis. Individual plants or small
populations can be removed by hand - pulling. If seed production occurs, prodigious
amounts of seed could be spread at the site.
GRASSES
Smooth Brome
Burn two years in a row (late- season burns in June) followed by seeding. This will usually
be sufficient to control smooth brome. (Remember to collect seed from on -site first, and if
there is not enough, then purchase local ecotype seed from off - site). Evaluate after the two
years. If this is not working, perhaps try a cool - season overspray of a grass- specific
herbicide either in the spring (April) or in the fall (October). Using glyphosate as a cool -
season overspray herbicide application is a last resort, since it kills everything.
Reed canary grass
Although not very prevalent at this site, this species should be controlled, since it is very
aggressive. At this site, it would not be as difficult to eradicate as in a wetland, but still will
probably require repeated treatment over a period of one to three years. A combination of
burning, chemical treatment and mowing can be used, in accessible areas, or chemical
treatment alone in inaccessible areas. The combination method starts by burning in late
spring to remove dead vegetation and to stimulate new growth. When new sprouts have
reached a height of 4 to 6 inches, the site can be sprayed with a 5% solution of a glyphosate
herbicide appropriate for wetland habitat (e.g. Rodeo). The site is then mowed in late
summer, followed by chemical application after re- growth. This treatment will stimulate
new growth and germination to deplete the seed bank. The sequence of chemical treatment
Friends of the Mississippi River 4 River Oaks Park NRMP
and mowing are repeated for at least a second season, and possibly a third until the grass is
completely eradicated. Then native grass and forb seed can be broadcast or drilled.
If reed canary is eradicated from an area, future management of the grassland, namely
burning, will likely keep the reed canary in check. Monitoring and mapping new
individuals or clumps should continue, however, and treated if burning is not adequate. If
the plants are small they can be removed by digging out the entire root. Generally though,
chemical treatment is more feasible. If plants are clumped, they can be treated by tying
them together, cutting the blades, and treat the cut surface with herbicide. Otherwise
herbicide should only be applied in native planted areas on very calm days to avoid drift to
non - target plants.
Friends of the Mississippi River 5 River Oaks Park NRMP
Appendix D. Ecological Contractors
Following is a list of contractors to consider for implementing the management plans.
While this is not an exhaustive list, it does include firms with ecologists who are very
knowledgeable with natural resource management. Unless otherwise noted, all firms do
prescribed burning. Many other brush removal companies are listed in the yellow pages
(under tree care), but most do not have knowledge or understanding of native plant
communities. We recommend hiring firms that can provide ecological expertise. Additional
firm listings can be found on the DNR website:
http: / /www.dnr. state. mn. us / gardens /nativeplants /index.html
Friends of the Mississippi River (FMR) has extensive experience working with landowners
to implement natural resource management plans. FMR can assist landowners with
obtaining funding for restoration and management projects and providing project
management, including contractor negotiations, coordinating restoration and management
work, and site monitoring and evaluation.
Applied Ecological Services, Inc.
21938 Mushtown Rd
Prior Lake, MN 55372
952 - 447 -1919
www.appliedeco.com
Bonestroo Natural Resources
2335 West Highway 36
St. Paul, MN 55113
651 - 604 -4812
www.bonestroo.com
Great River Greening
35 West Water St, Suite 201
St. Paul, MN 55107
651 - 665 -9500
www.greatrivergreening.org
Minnesota Native Landscapes, L.L.C. 14088 Highway 95 N.E.
Foley, MN 56329
(320) 968 -4222 Phone www.mnnativelandscapes.com
Conservation Corps Minnesota
2715 Upper Afton Road, Suite 100
Maplewood, MN 55119
(651) 209 -9900
Friends of the Mississippi
River Oaks Park NRMP
1
Wetland Habitat Restoration
1397 Chelmsford St.
St. Paul, MN 55108
612 - 385 -9105
www.whr.mn
Prairie Restorations, Inc.
PO Box 305
Cannon Falls, MN 55009
507 - 663 -1091
http: / /www.prairieresto.com/
Friends of the Mississippi
River Oaks Park NRMP
PA
Southern Dry -Mesic Oak Forest (MHs37)— cont'd
Friends of the Mississippi River 4 River Oaks Park NRMP
Genus Species
Common Name
Canopy Trees &
understory trees
Acer neg undo
Betula papyrifera
Box elder
j Paper -birch
t
_
Carya cor diformis
Celtis occidentalis
Fraxinus pennsylvanica
Bitternut hickory
( Ha ckberry
Green ash
--
Os trya 1 virginiana
j Ironwood
Populus grandidentata
Populus c tremuloid
Big toothed as pen
Quaking aspe j
j
Prunus serotina
Black cherry
Quercus alba
Quercus ellipsoidalis
White oak
Northern pin oak
Quercus - macroc
Bur oa
Quercus I rubra
Northern red oak
Tilia americana
Basswood
f
_
Ulmus americana ^ American
elm
Ulmus rubra
red elm
Shrubs
Amelanchier j interior
Juneberry
Am j laevis
Smooth jun eberr y
Co rpus j alternifolia j
- --
Comu rugosa _
Corpus racemosa
Pag do gwood
j Rou leaved d ogwood
Gray dogwood _
j
Corylus - i a mericana
Cory/us I cornuta
j American haz elnut
Beaked hazelnut
Crataegus cmx
Hawthorn
Diervilla lonicera
— - - --
_ Bush hone
Ilex j verticillata
Winterberry
_
Lonicera E dioica
Prun virginiana
Wild Honeysuckle
Chokecherry _
Ribes cynosbati
Prickly gooseberry
-
Ri missouriense j
Rosa arkansan
Rosa blanda j
Rubus 1 occidentalis j
- --
Missouri gooseberry
Prairie rose
Smoo wild ros
Black raspberry
Rubus idaeu
Red raspberry
Sambucus racemosa j
Red- berried E lder
Symphoncarpos alba _
Viburnu lentago {
Snowberr
Nannyberry
- - — —
Viburn rafnesquianum _ Downy arrow wood _ i
Friends of the Mississippi River 4 River Oaks Park NRMP
Southern Dry -Mesic Oak Woodland (FDs37)
Scientific name
Forbs
Amphicarpaea bracteata
Antenaria spp.
Anemone americana
Anemone quinquefolia
Apocynum androsaemifolium
Aquilegia Canadensis
Aralia nudicaulis
Aster cordifolius
Aster macrophyllus
Aster sagittifolius
Athyrium filix- femina
Campanula rotundifolia
Carex pensylvanica
Circaea lutetiana
Desmodium glutinosum
Eupatorium rugosum
Euphorbia corollata
Fragaria virginiana
Galium boreale
Galium triflorum
Geranium maculatum
Geum canadense
Helianthus strumosus
Maianthemum canadense
Osmorhiza claytonii
Osmunda claytoniana
Pteridium aquilinum
Phryma leptostachya
Polygonatum biflorum
Pyrola elliptica
Sanicula gregari
Sanicula marilandica
Smilacina racemosa
Solidago ulmifolia
Thalictrum dioicum
Trientalis borealis
Uvularia grandiflora
Uvularia sessilifolia
Common name
hog - peanut
pussytoes
round -lobed hepatica
Wood anemone
Spreading dogbane
columbine
wild sarsaparilla
heart- leaved aster
Large - leaved aster
Tail- leaved aster
lady fern
harebell
Pennsylvania sedge
enchanter's nightshade
pointed - leaved tick - trefoil
white snakeroot
flowering spurge
wild strawberry
northern bedstraw
three - flowered bedstraw
wild geranium
white avens
woodland sunflower
Canada mayflower
sweet cicely
Interrupted fern
Bracken fern
lopseed
Giant Solomon's seal
Elliptic shinleaf
gregarious black snakeroot
Maryland black snakeroot
false Solomon's seal
elm- leaved goldenrod
Early meadow rue
Starflower
Large flowered bellwort
Pale bellwort
Grasses and Sedges
Carex pensylvanica
Pennsylvania sedge
Oryzopsis asperifolia
Festuca subverticillata
Elymus hystrix
Shrubs
Amelanchier spp.
Cornus alternifolia
Corpus racemosa
Cornusrugosa
Corylus americana
Corylus cornuta
Diervilla lonicer
Prunus virginiana
Prunus pennsylvanica
Ribes cynosbati
Sambucus racemosa
Symphoricarpos albus or occidentalis
Viburnum lentago
Viburnum rafenesquianum
Xanthoxylum americanum
Mountain rice grass
Nodding fescue
Bottlebrush grass
Juneberries
Pagoda dogwood
Gray dogwood
Round - leaved dogwood
American hazelnut
Beaked hazelnut
Bush honeysuckle
Chokecherry
pin cherry
Prickly gooseberry
Red berried elder
Snowberry /wolfberry
Nannyberry
Downy arrowwood
Prickly ash
Trees
Betula papyrifera
Paper birch
Carya cordiformes
Bitternut hickory
Celtis occidentalis
Hackberry
Ostrya virginiana
Ironwood
Prunus serotina
Black cherry
Quercus alba
White oa k
Quercus ellipsoidalis
N orthern pin oak
Quercus macrocarpa
Bur oak
Quercus rubra
Northern red oak
Friends of the Mississippi River 5 River Oaks Park NRMP
Southern Mesic Savanna (UN24)
Genus Species
Trees
Quercus macrocarpa
Shrubs
Amorph
c
Prunu s - ________j
virginiana
Rosa j a
_
Salix humilis
Symphori-
carpos abla
Grasses, Rushes and Sedges
Andropogon
gerardi
Bromus
1 kalmii
Carex
-- -
; bicknellii
Carex
Fmeadii -
Carex
Euphorbia corollata
Elymus
_mu_hlen
canadensis
-
Dicantheliu
perlong
Panicum virgatum
Schizachyrium scoparium
Sorghastrum nutans
- -- �_ -
Sp he
Stipa spartea
Forbs
Allium
j can adense
Allium
s tel latu m
_
Anem one
canade
Anemon
cylindrica
Anemo
I vir i3 nia na_
Antennaria
species
Fern Allies
Androsae-
Apocynum
mif
Artemisia -
ca
Artemisia i
fripida
Ascle pias
t ub er osa
Aster
ericoides
Aster
laevis
Aster
lan ceolatus
Aster
novae - angh
A ster
oolentangie
Astragalus
canadensis
C ampanula .
rotun _qiyoha
Coma
umbellat
Coreopsis __ (_pal -
Dalea cand ida
Dalea - - p urpurea
Desmodium canadense
Euphorbia corollata
Euthamia araminifolic
Common Name
Forbs (cont'd)
Fragar j virginiana ( Common strawberry
Galiu - j _ borea le Nor thern bedstraw
Ge ntian a x I billin gtomi I Closed gentian
(_ Gayfea t her _
Bur oak
Lead plant
Chokecherr
Geum triflorum Pra smoke
- -- -- - -
Heli anthus maximiliani Maximilian's sun flower
_-_k-_-
Prairie rose
- --�-_ - -- -
Prairie willow
Snowberry
Heli anthus I
r
-p aucitlous
; Stiff sunflo
Helio sis
helianthoides
( Ox -e ye - - - - --
Hete rotheca
villosa
--
Prairie golden aster
Heuchera
richardso
+Alum-r
Lathyrus
venosu
Veiny pea
Big luestem
g
Lespedeza 1
capitata
Round- headed
bush - clover
--
Kahn's brome
-
Lia -
- -
- - - -
) aspera
-
- -- - -- -
i Rough bla star
--
- -_ - -.-
Bicic sedge_
M ead' sedge
Liatris
ligulistylis
Northern plains
I blazing star
Muhlenberg sed
Canada wild rye
Long - leaved
panic grass _
Switchgrass
Little bluestem
Indian gras
P rairie dropsee
Porcupine -grass
Wild garlic
Prairie wild onion
Canada anemon
Long- headed
thimbleweed
Virginia thimblew
Tall wormwood
Prairie sagewort
Common milkweed
Butterfly weed _
Liatris
-
py cnostac hya
(_ Gayfea t her _
Gray goldenrod
Philadel-
C
Lilium
phicum
Wood lily
Lobelia
spca
Rough - sp iked Lobelia
Maian-
pinnata
L coneflower --
themum
racemosum
I False Solomon's -se
Ma ian
Lc ampestr e ____I
Starry false
themum j
stellatum
Solomon's -s eal i
-
Mirabilis
hir us a 1
Hairy f
Monarda
- rda
iistulosa -
- -- --
Wild ber gamot
virginicum
-
Common evening-1
Oenothera
bienn I
p rimros e
Pedicularis
canadensis
Wood - betony
Phlox
pilosa
Prairie phlox
Phvsalis
heteronhvlla
Clammv ground - cher
Potentill
_Pycnan
ar guta -
Ta ll cin -- -
Gray goldenrod
Smooth aster
-_
themum
virg
Virg inia mountain -mint
Solida
A ptarmicoides
Gray- headed 1
Ratibida
- id
pinnata
L coneflower --
Rudbeckia j
hirta
Black -eyed Susan j
Sis yrinchium
Lc ampestr e ____I
Field blue -eyed grass
Solidago ]
miss ouriensis
I Missouri goldenrod 1
Heath aste
Solidago
nemorahs
Gray goldenrod
Smooth aster
-_
Upland white
Panicle aster - - -
Solida
A ptarmicoides
goldenrod
New England ast
Solidago
sped . osa
Showy goldenrod
Sky -blue aster _
Thalictrum
dasycarpum
Tall meadow -rue
Canada milk-vetc
Tradescantia
bracteata
Bracted spiderw
Harebell
Veroni-
_
Bastard toad -flax
castrum
virginicum
Culver's ro
Stiff tickseed
Viola
--- - - - -
pedati
-- - --
( Prairi bird -foot v iolet
- - - --
Wh ite prairie - clover
Zizia
aurea
Golden alexanders
Purple p rairie - clover
Ferns and
Canadian tick- trefoil
Fern Allies
j
Flowerin spurge
Equisetum
I arve nse
;F ield h
Grass-lv goldenro
Equisetu
hyemale
( Tall scouring - rush
Equisetum
( laevigatum
j Smooth scouring -rush
Friends of the Mississippi River 6 River Oaks Park NRMP
Appendix C. Methods for Controlling Exotic, Invasive Plant Species
TREES AND SHRUBS
Common Buckthorn, Tartarian Honeysuckle, Siberian Elm, and Black Locust are some of
the most common woody species likely to invade native woodlands or prairies in
Minnesota. Buckthorn and honeysuckle are European species that escaped urban
landscapes and invaded woodlands in many parts of the country. They are exceedingly
aggressive and, lacking natural disease and predators, can out - compete native species.
Invasions result in a dense, impenetrable brush thicket that reduces native species
diversity.
Siberian elm, native to eastern Asia, readily grows, especially in disturbed and low- nutrient
soils with low moisture. Seed germination is high and seedlings establish quickly in sparse
vegetation. It can invade and dominate disturbed areas in just a few years. Black locust is
native to the southeastern United States and the very southeastern corner of Minnesota. It
has been planted outside its natural range, and readily invades disturbed areas. It
reproduces vigorously by root suckering and can form a monotypic stand.
Chemical Control
The most efficient way to remove woody plants that are 1/2 inch or more in diameter is to
cut the stems close to the ground and treat the cut stumps with herbicide immediately after
they are cut, when the stumps are fresh and the chemicals are most readily absorbed.
Failure to treat the stumps will result in resprouting, creating much greater removal
difficulty.
In non - freezing temperatures, a glyphosate herbicide such as "Roundup" can be used for
most woody species. It is important to obtain the concentrated formula and dilute it with
water to achieve 10% glyphosate concentration. Adding a marker dye can help to make
treated stumps more visible. In winter months, an herbicide with the active ingredient
triclopyr must be used. "Garlon 4" is a common brand name and it must be mixed with
penetrating oil, such as "diluent blue ". Do not use diesel fuel, as it is much more toxic in the
environment and for humans. (Caution: it is not recommended to use Garlon 4 in the bluff
prairie, since it tends to create a "kill ring" at the base of the treated stem. The bluff prairie
has too great an abundance and diversity of native plants to allow it to be damaged by
herbicide kill rings. Use of Garlon 4 is acceptable in the woodland areas of the property,
however, where the abundance of natives is not very high.)
Brush removal work can be done at any time of year except during spring sap flow, but late
fall is often ideal because buckthorn retains its leaves longer than other species and is more
readily identified. Cutting can be accomplished with loppers or handsaws in many cases.
Larger shrubs may require brush cutters and chainsaws, used only by properly trained
professionals.
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For plants in the pea family, such as black locust, an herbicide with the active ingredient
clopyralid can be more effective than glyphosate. Common brand names for clopyralid
herbicides are "Transline ", "Stinger ", and "Reclaim ".
In the year following initial cutting and stump treatment, there will be a flush of new
seedlings as well as resprouting from some of the cut plants. Herbicide can be applied to
the foliage of these plants. Fall is the best time to do this, when desirable native plants are
dormant and when the plant is pulling resources from the leaves down into the roots.
Glyphosate and Krenite (active ingredient - fosamine ammonium) are the most commonly
used herbicides for foliar application. Krenite prevents bud formation so the plants do not
grow in the spring. This herbicide can be effective, but results are highly variable.
Glyphosate or a triclopyr herbicide such as Garlon can also be used. Glyphosate is non-
specific and will kill anything green, while triclopyr targets broadleaf plants and does not
harm graminoids. All herbicides should be applied by licensed applicators and should not
be applied on windy days. Care should be taken to avoid application to other plants. "Weed
Wands" or other devices that allow dabbing of the product can be used rather than
spraying, especially for stump treatment.
Undesirable trees and shrubs can also be destroyed without cutting them down. Girdling is
a method suitable for small numbers of large trees. Bark is removed in a band around the
tree, just to the outside of the wood. If girdled too deeply, the tree will respond by
resprouting from the roots. Girdled trees die slowly over the course of one to two years.
Girdling should be done in late spring to mid - summer when sap is flowing and the bark
easily peels away from the sapwood. Herbicide can also be used in combination with
girdling for a more effective treatment.
Basal bark herbicide treatment is another effective control method. A triclopyr herbicide
such as 10% Garlon 4, mixed with a penetrating oil, is applied all around the base of the
tree or shrub, taking care so that it does not run off. If the herbicide runs off it can kill other
plants nearby. More herbicide is needed for effective treatment of plants that are four
inches or more in diameter.
Mechanical Control
Three mechanical methods for woody plant removal are hand pulling (only useful on
seedlings and only if few in number), weed wrenching (using a weed wrench tool to pull
stems of one to two inches diameter), and repeated cutting. Pulling and weed wrenching
can be done any time when the soil is moist and not frozen. The disadvantage to both
methods is that they are somewhat time - consuming, as the dirt from each stem should be
shaken off. Weed wrenching also creates a great deal of soil disturbance and should not be
used on steep slopes or anywhere that desirable native forbs are growing. The soil
disturbance also creates opportunities for weed germination. This method is probably best
used in areas that have very little desirable native plant cover.
Repeated cutting consists of cutting the plants (by hand or with a brush cutter) at critical
stages in its growth cycle. Cutting in mid spring (late May) intercepts the flow of nutrients
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from the roots to the leaves. Cutting in fall (about mid - October) intercepts the flow of
nutrients from the leaves to the roots. Depending on the size of the stem, the plants
typically die within three years, with two cuttings per year.
Stems, Seedlings and Resprouts
Prescribed burning is the most efficient, cost effective, and least harmful way to control
very small stems, seedlings, and resprouts of all woody plants. It also restores an important
natural process to fire - dependant natural communities (oak forests, for example). Burning
can only be accomplished if adequate fuel (leaf litter) is present and can be done in late fall
or early spring, depending site conditions.
If burning is not feasible, critical cutting in the spring is also effective, though it can impact
desirable herbaceous plants as well. Foliar (leaf) application of a bud - inhibitor herbicide
(Krenite) during fall is also effective. This method can also affect non - target species, though
most natives will be dormant by that time.
Prickly ash
A native shrub, prickly ash can become excessively abundant, especially in areas that have
been disturbed or grazed. Complete eradication may not be necessary, but management
may target reducing the extent of a population. Removal is most easily accomplished in the
same manner as for buckthorn - cutting shrubs and treating cut stumps with glyphosate
herbicide. Cutting can be completed at any time of the year.
Disposal
The easiest and most cost - effective method to handle large amounts of brush is usually to
stack it and burn it in winter. In areas where brush is not dense, it can be cut up into
smaller pieces and left on the ground where it will decompose in one to three years. This
method is especially useful on slopes to reduce erosion potential. Small brush piles can also
be left in the woods as wildlife cover. Where there is an abundance of larger trees, cut trees
may be hauled and chipped and used for mulch or as a biofuel. Alternatively, the wood can
be cut and used for firewood, if a recipient can be found.
FORBS
Canada thistle
While native thistles are not generally problematic, exotics such as Canada thistle are
clone - forming perennials that can greatly reduce species diversity in old fields and
restoration areas (Hoffman and Kearns 1997). A combination of chemical and mechanical
control methods may be needed at the Empire property. Chemical control is most effective
when the plants are in the rosette stage and least effective when the plants are flowering. A
broadleaf herbicide such as 2,4 -D would be appropriate for the south grassland (G1), to
minimize damage to native grasses. It is most effective when applied 10 -14 days before the
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