15-Attachment M Kohl Park ERMP Final.pdf

Kohl Park Wildlife Enhancements Project Ecological Restoration & Management Plan

Prepared by Natural Areas and AOC Staff

MILWAUKEE COUNTY PARKS

Table of Contents Kohl Park Ecological Restoration and Management Plan

Overview

AOC, BUI, and Project Background

Area of Concern

Focal Species and the Degradation of F&W Populations BUI

Why Kohl Park?

Project Goals and Objectives

Site Information

Historic Vegetative Communities

Soils

Wetlands

Wildlife

Assessment of Current Conditions

Southern Mesic Forest

Grassland and Shrub-Carr

Conifer Plantation

MCP Plant Database

Restoration Potential Overview

Restoration Actions

Habitat Community Types Restoration

Southern Mesic Forest Restoration and Expansion

Overview:

Deciding Process for SMF Restoration Action Goals

Target Restoration Actions

Grassland and Shrub-Carr Management

Overview

Deciding Process for Grassland and Shrub-Carr Restoration Action Goals

Target Restoration Actions

Conifer Management Area

Overview:

Deciding Process for Conifer Restoration Action Goals

Target Restoration Actions

Conclusion

References

Appendices

Kohl Park Project Timeline

Kohl Park Estimated Costs

Table 1 – Kohl Park Plant Inventory

Table 2 – Southern Mesic Forest Planting Recommendations

Table 3 – Shrub-carr and Prairie Planting Recommendations

Table 4 – Conifer Planting Recommendations

Table 5 – Focal Species Evaluation Matrix .................................................................................................. XX

Table 6 – Priority Invasive Species .............................................................................................................. XX

Kohl Park Ecological Restoration and Management Plan

Overview Within this document is the blueprint for enhancing and restoring the natural areas at Kohl Park, located on Milwaukee County parkland, for the benefit of native wildlife. This plan is not all-inclusive, rather it details a number of actions that will progressively move the natural areas toward a more ecologically stable state in which native wildlife populations have the opportunity to stabilize and expand.

Despite a history of ecological and environmental degradation, plant and wildlife populations persist at Kohl Park, as seen by the recent and comprehensive flora and fauna surveys funded by the Great Lakes Restoration Initiative (GLRI) Area of Concern (AOC) program. However, when compared to other natural areas with higher quality wildlife habitat within the park system, Kohl Park only has a fraction of that variety of wildlife. This indicates that the current conditions, while not bleak, present an opportunity for restoration and management efforts aimed at enhancing the site for important native wildlife species.

This practical plan recognizes that ecological restoration is essential to the improvement of habitat at Kohl Park, to achieve the AOC metrics for removal of the Degradation of Fish and Wildlife (F&W) Populations Beneficial Use Impairment (BUI), and to accomplish the Milwaukee County Parks (MCP) ecological goals for the project site. This plan is a compilation of actions that are logistically feasible, sustainable, actionable, and ecologically appropriate based on what is currently known about Kohl Park.

AOC, BUI, and Project Background Area of Concern In 1987, the Milwaukee Estuary was designated as one of 43 Great Lakes AOCs under the Great Lakes Water Quality Agreement between Canada and the United States. An AOC is an area that has experienced environmental damage and habitat loss – to the point where humans, fish, and wildlife are unable to fully use the natural resources in a safe or beneficial way. The objective of the AOC program is to prioritize remediation and restoration efforts in the most impaired parts of the Great Lakes. The Milwaukee Estuary AOC encompasses the inner and outer harbors, nearshore waters, and stretches of the Milwaukee, Menomonee, and Kinnickinnic Rivers.

In order to remove the AOC designation from the Milwaukee Estuary, a set of 11 (out of 14 possible) BUIs must be addressed. Enhancing habitat for fish and wildlife populations in multiple project areas, including Kohl Park, has been identified as a management action for the Degradation of F&W Populations BUI. As defined by the U.S Environmental Protection Agency (EPA), “this BUI works to restore environmental conditions to support healthy, self-sustaining communities of desired fish and wildlife at levels of abundance predetermined locally. These levels are set based on what would be expected from the amount and quality of suitable physical, chemical, and biological habitat present in the AOC.” In order to achieve this, each project under this BUI designation will need to demonstrate management actions that support the increase of focal species populations.

Focal Species and the Degradation of F&W Populations BUI From 2014-2017, a wildlife population assessment was conducted across the Milwaukee Estuary AOC to establish a baseline species inventory, determine local occurrence, and aid in the establishment of specific management actions to support eventual BUI removal. Following the assessment, BUI removal criteria was developed in conjunction with the Milwaukee Fish and Wildlife Technical Advisory Committee (Tech Team). These metrics outline the number of sites and species to be supported to consider the wildlife populations no longer impaired due to AOC specific impacts. Throughout this process, the Tech Team identified 11 focal species groups that would benefit from habitat restoration work within the AOC.

Focal species groups that were present at Kohl Park during this initial wildlife assessment are listed in Table 1 below and further identified in the appendices, Table 5 Focal Species Evaluation Matrix.

Table 1. Focal Species Present in Kohl Park

Priority Focal Species Groups in AOC Present in Kohl Park (2014-2017)

Breeding Birds (forest, wetland, shrubland, grassland) X Burrowing Crayfish

Frogs X Turtles Snakes X

Salamanders Mammals

Fish

Using the focal species groups and considering how potential restoration and enhancement goals would improve or provide habitat, project specific lists of focal species were developed to represent the species that would most benefit from future work in a project area. Since the majority of the Milwaukee Estuary AOC is within a highly urbanized area, the goal is to ensure that areas remain for these rare and locally important species (MacLellan-Hurd, 2022). With this, only actions that provide a direct benefit to project-specific focal species can be conducted.

Each restoration action will focus on improving habitat for project specific focal species. The focal species identified in the Focal Species Evaluation Matrix (Appendix Table 5 Focal Species Evaluation Matrix) are those with habitat requirements that reflect restoration and enhancement goals for the project area. Therefore, the connection between a restoration action and the potential benefit must be verified and documented.

The current status of focal species and the BUI metrics for them are as followed:

• DO NO HARM: Kohl Park is meeting the airspace/urban breeding bird metric and the frog metric. These species cannot be harmed, reduced and/or impacted through restoration actions in order to continue to meet the metrics upon project completion.

• Improve/Add: Kohl Park must support each of the following focal species groups populations in order to address the breeding bird metrics.

o forest breeding birds, o wetland breeding birds, o shrubland/edge breeding bird, o grassland breeding bird.

• Improve/Add: Kohl Park must support snake species populations in order to address the snake metrics.

Why Kohl Park?

The Milwaukee County Department of Parks, Recreation, and Culture (hereafter referred to as MCP) has management oversight for Kohl Park located within Milwaukee County, Wisconsin and is divided by 76th street, creating an east and west side. County Line Road is directly north of the property and separates Milwaukee County from Ozaukee County (Appendix Figure 1).

The land surrounding Kohl Park is a mix of natural areas (Mequon Nature Preserve to the north), residential, and commercial. The project area falls within T8N, R21E, and Sections 3 & 4.

Kohl Park is located within the Milwaukee River Watershed, on the northern boundary of the Milwaukee Estuary AOC, and within the Southern Lake Michigan Coastal Ecological Landscape (WI DNR). There are a total of 231.9 acres to be restored at Kohl Park comprised of 98.5 acres of natural areas and 133.4 acres of previously leased agricultural fields (to be converted to natural areas). This total acreage excludes the ~50 acres leased to UW Extension’s community gardens program. Kohl Park is managed by MCP, and MCP will be in charge of the long-term maintenance of this project. This acreage has been broken down into 11 management units (Appendix Figure 2), shown below in Figure 2 and Table 2, developed to represent the future vegetation areas as described in this plan.

Currently, Kohl Park contains a segment of the MCP Forked Aster hiking trail that runs through management units 10 and 11, this trail is 3,500 linear feet. A segment of the Oak Leaf Trail (OLT) will be constructed in 2025 throughout the entire property (Appendix Figure 26) which will result in a slight reduction of acreage for this AOC project. In addition to the recreational trails, there is also approximately 50 acres that is outside of this project scope (Appendix Figure 3). This land is leased to UW-Extension’s Community Garden program and will remain as such.

Kohl Park was chosen as an AOC Project Area due to the following:

• Large size (approximately 266 acres in total),

• Opportunity to convert formerly leased agriculture land to grassland/prairie, a habitat type that is extremely rare in the Milwaukee Estuary AOC,

• Proximity to other large tracts of protected properties, creating a habitat corridor for wildlife,

• One of only three project areas in the AOC that will support grassland and airspace/urban breeding bird groups.

Through the conversion of old agricultural lands, this project aims to create unique wildlife habitats that will be essential to address the wildlife population impairments in the AOC. On top of this, Kohl Park falls within the Southeastern Wisconsin Regional Planning Commission (SEWRPC) designated “Environmental Corridor” and contains several designated “Isolated Natural Resource Areas” which are areas of at least five acres, containing a significant concentration of natural resources, and are separated from the environmental corridor by urbanization or agriculture. This project area is surrounded or connected to other large parcels of land such as Mequon Nature Preserve, Little Menomonee River Parkway, AC Hanson, and Milwaukee Metropolitan Sewerage District (MMSD) Greenseams parcels. Through the restoration and enhancements of Kohl Park, a habitat corridor of over 1,000 acres will be intact and usable for native wildlife.

In addition, portions of Kohl Park will also be designated “Critical Species Habitat” areas in the soon to be released SEWRPC’s Regional Natural Areas Plan update (available September 2025), due to the presence of state and federally listed species observed by MCP Natural Areas staff while conducting in-depth surveys of the site in the past several years. This recent designation emphasizes the importance of this project site.

Project Goals and Objectives The goal of this Ecological Restoration and Management Plan (ERMP) is to describe potential restoration and management actions that will protect ecologically significant natural areas at Kohl Park to benefit focal species in order to address the Milwaukee Estuary AOC Degradation of F&W Populations BUI metrics. The following objectives are put forward to ensure the goal is achieved:

• Restore habitats with increased native plant species to improve ecological conditions that support breeding birds, snakes, and frogs that are present or are likely to be present at Kohl Park.

• Control large populations of woody and herbaceous invasive plant species to reduce their negative impact on focal species.

• Enhance and maintain the existing significant natural resources present at Kohl Park to ensure the continued SEWRPC designation as an environmental corridor.

• Implement restoration actions that address the following:

o BUI Removal Metrics o MCP Priority Species

Figure 1: Kohl Park Boundaries (Appendix Figure 1)

Figure 2: Kohl Park Management Units (Appendix Figure 2)

Table 2. Kohl Park Management Units and Acreage

Management Unit Acres Existing Vegetation

1 2.9 Surrogate Grassland, Degraded/Disturbed

2 11.0 Southern Mesic Forest, Degraded/Disturbed, Southern Hardwood Swamp

3 14.0 Turf Grass, Agriculture Field, Degraded/Disturbed

4 3.9 Degraded/Disturbed

5 9.7 Degraded/Disturbed

6 6.6 Shrub Carr Degraded/Disturbed

7 59.3 Surrogate Grassland, Agriculture Field, Degraded/Disturbed

8 1.1 Surrogate Grassland

9 70.0 Mesic Prairie, Agriculture Field, Degraded/Disturbed

10 26.9 Southern Mesic Forest, Degraded/Disturbed

11 25.7 Conifer Plantation

Site Information Historic Vegetative Communities Wisconsin public land survey records (1836 Board of Commissions Public Lands) show that Kohl Park, which was referred to as “Good rolling land,” was predominantly upland forest. Regularly occurring species within the surveyor notes were: White Oak, Bur Oak, Sugar Maple, American Basswood, “elm”, and Butternut. Black Ash was also a species listed as present, even though no wetland complexes were drawn out by surveyors. Overall, these species are indicative of a southern mesic forest (SMF), which persist in small remnants at Kohl Park.

Terrestrial degradation that has historically occurred over the past hundreds of years at this site including logging, dumping, and near complete conversion to agriculture. The 1928 aerial photo (WI Historical Aerial Imagery Finder) shows that virtually all the natural areas currently within the boundaries of Kohl Park, with the exception of small pockets of woodlands, were non-existent and that farmland covered over 95% of the site (Figure 3). During this time when Kohl Park was covered in agricultural fields, a limited variety of wildlife would have been utilizing this area. Farming operations on site have largely ceased and the land was allowed to “naturalize;”

yet the presence of non-native plant species, coupled with browsing impacts of white-tailed deer, has resulted in the persistence of degraded conditions. Despite a long history of anthropogenic impacts, nature at Kohl Park has been resilient. The remnant SMF, shrub-carr, and hardwood swamp communities have persisted since at least 1928. As these habitats began to come back, although degraded, wildlife utilizes them for nesting, foraging, migratory stopover, etc.

Figure 3 Kohl Park 1928 Aerial

Historically, the woodlands that covered nearly all of Kohl Park were SMF. The oldest available aerial photo (1928) shows that the eastern SMF (MU2) existed as a dense closed canopy very similar to today’s woodland, but the western SMF (MU10) consisted of large open grown trees (likely the oldest sugar maples and red oaks found in that SMF today) around a former homestead. Once the homestead was removed, a dense monoculture of American basswoods filled in and are still present. The western SMF (MU10) eventually attained canopy closure in the mid-1990s and has stayed relatively intact since then with the exception of small pockets of ash species which have succumbed to EAB.

Within Milwaukee County northern red oak, white ash, and black cherry would also have been common canopy trees in SMF. Drier soils within this SMF would likely have contained populations of white oak and shagbark hickory as codominant canopy trees as well. The once dominant upland forest plant community, present in the mid-1800s, has been virtually eliminated from Kohl Park. Yet, four small, degraded, and tattered remnant SMF remain (13.1-acres total), which equates to a 94% loss of forest coverage.

In the 1928 aerial photos, there is some evidence of shrub-carr habitat showing up in MU6, as well as visual evidence of a man-made ditch installed to drain this area during the same time period. The ditching persists today, but it is unclear if it has the same functionality due to large trees growing within the ditch and what appears to be soil material being dumped near the historic outlet at County Line Road. As wetland habitat began to naturally appear, this would bring many wetlands and shrubland species back to Kohl Park, such as frogs, salamanders and birds that rely on wetlands and shrub-carr habitats for breeding and nesting purposes. Many of those species are found today at Kohl Park (Appendix Table 5 Focal Species Matrix).

A prairie in the southwest corner of MU9 appears to have been planted between 1980-1990, according to historical aerial imagery. Unfortunately, no MCP internal records exist concerning the planting of the prairie. To the best of our knowledge, the planted prairie has never been burned. It does contain one stated listed species that is also found at other locations at Kohl Park, but it is a species that typically likes some disturbance to persist.

Another introduced plant community is the historic conifer plantation in the very northwest corner of the site (MU11). The conifer plantation was SMF according to the surveyor maps from 1836. The southern half of the existing conifer plantation (Scotch pine and variety of spruce species) was likely established around 1970, and the northern half was planted around 1980 or slightly earlier. Prior to the plantings the management unit was treeless and entirely farmed (Historic aerial photos 1928-1980) and no other vegetation was present. Within this 25.7-acre management area, the conifers failed to establish in 6.8-acres in the north central part of the historic planting (Appendix Figure 12). Most of the tree failure corresponds with a seasonal drainageway and/or seasonally moist soil areas. The soils were likely too wet for the conifer species that were planted which were predominantly Norway spruce, white spruce, and Scotch pine.

Soils The most prevalent soil types at Kohl Park are Ozaukee Silt Loam (56%), Mequon silt loam (29%), Ashkum silty clay loam (10%), and Martinton Silt Loam (5%) with smaller concentrations of Aztalan Loam and Hebron Loam (<1%) as described by United States Department of Agricultural Natural Resource Conservation Services (USDA-NRCS) (Appendix Figure 6 and Figure 17). Below is a brief breakdown of the major soil series types.

• Ozaukee Silt Loam is a moderately well drained soil but does have potential for medium-high surface water runoff. Common trees that thrive in this soil are northern red oak, white ash, sugar maple, and American basswood.

• Mequon Silt Loam has high potential of run-off given that it is a poorly drained soil type.

Hardwood forests species tend to grow well in these conditions.

• Ashkum Silty Clay Loam was formed in colluvial sediments (USDA-NRCS) which makes it poor draining. There typically is a high-water table associated with this soil, making runoff potential low. Sedge and grass species typically associated with wetlands, grasslands and prairies grow well in this soil.

• Martinton Silt Loam is associated with crop cultivation and prairie grass. This soil type is poorly drained with slow permeability.

Wetlands Three wetland types have been delineated by WI DNR and/or SEWRPC at Kohl Park and include forested, emergent/wet meadow, and scrub/shrub wetlands (Appendix Figure 7 and Figure 18).

All delineated wetlands have been compromised, to varying levels, by dense stands of non-native cattails (narrow-leaved and hybrid), reed canary, and/or common buckthorn. Other wetland invasives such as common reed grass (Phragmites) are present, but at this point remain at low levels likely due to fluctuating water levels and suppression by the buckthorn and non-native cattails that likely established first given their current population sizes and densities. These invasive plant species have the ability to alter the hydrology in wetlands which in turn effects the way aquatic and semi-aquatic wildlife are able to use this habitat type throughout their life cycle at this site (e.g. breeding locations, food, habitat). Wetlands are also important habitat for mammals and birds. In addition, there are 12 potential ephemeral ponds, and 3 have been historically surveyed by MCP Natural Areas staff. Ten of the ephemeral ponds are east of 76th Street and two are located west of 76th Street. Gray Tree Frog, Northern Green Frog, and Northern Leopard Frog have been confirmed to be breeding within several ponds east of 76th Street – a focal species group for this project.

Wildlife As an AOC project, each restoration action must benefit one or more focal species, demonstrating that focal species populations are the first and most critical component to this project.

It is important to note that historic research in the upper Midwest targeted non-urban wildlife populations and, in most cases, didn’t factor in the impacts of rapidly changing weather patterns.

While more researchers are starting to focus on urban wildlife populations, it is still rather minor when compared to the more traditional research done on non-urban wildlife populations. It is important to remember that urban wildlife populations often occur within novel plant communities, and this plan recognizes that reality. Currently, the best habitat use information available comes from the initial AOC wildlife surveys, recent WI Breeding Bird Atlas II surveys, and research done by MCP and project partners within the AOC boundaries and within the larger MCP System.

The AOC wildlife inventory conducted by MCP staff and contractors (2014-2024), as well as, long-term monitoring by the MCP and Community Science volunteers have documented: 6 species of amphibians, 127 species of birds, 7 species of bumble bees, 22 species of butterflies, 1 species of crayfish, 13 species of mammals, 24 species of odonates (dragonflies and damselflies), and 1 species of snake utilizing Kohl Park during their annual lifecycles. This includes seven state and/or federally listed species of wildlife (crayfish, snake, frog, bumble bees, damselfly, and butterfly) documented at Kohl Park since 2021. An additional nine species of state listed birds have been documented using Kohl Park during migration. Altogether, a minimum of 200 species of wildlife have been documented using the existing habitat at Kohl Park.

Within the 200 wildlife species previously documented, this project is anticipated to benefit 24 focal species that are currently supported or have the potential to be supported at the site. Focal species for Kohl Park fall into the following groups: forest, wetland, shrubland/edge and grassland breeding birds, crayfish, frogs, snakes, and mammals. Through enhancements of vegetative communities, focal species will see many positive long-term impacts, such as improved nesting site quality, increased food sources, and reconnection of habitat. Measures of success are related to focal species populations’ responses to the restoration efforts on the landscape.

As previously mentioned, the focal species groups and the individual species within the groups were determined based off which species were currently utilizing Kohl Park and nearby. Species were also determined based on potential restoration actions and habitats that could support additional wildlife in the future. Additional consideration was given to what the project area could look like after restoration – this includes creating grassland habitat and improvements, reforestation, invasive species removal, and wetland enhancements. Improving grassland breeding birds’ populations and required habitat was a large focus for the AOC and this project specifically. Within the Milwaukee Estuary AOC, there are not many opportunities to provide large, contiguous tracts of grassland for the species that depend on it. Kohl Park offered a solution through the conversion of old agricultural fields. This allowed the AOC team to focus on focal species that will greatly benefit from this grassland/prairie development. When prioritizing restoration actions, not only do the long-term benefits to focal species need to be considered, but also what will best cater to remove the BUI.

Assessment of Current Conditions The Kohl Park of today is drastically different than in the past in its composition of habitats and plant communities. Vegetative surveys conducted in 2021-2024 by MCP staff delineated the following cover types: agricultural row-crops, conifer plantation, hardwood swamp, mesic prairie (historically planted), shrub-carr, SMF, surrogate grassland, turf grass, and large areas of degraded habitat (Appendix Figure 12 and 23). Degraded habitat as defined by MCP is a vegetative cover type that consists of 75% or greater coverage by non-native herbaceous and woody invasive species. The degraded cover type was by far the dominant cover type at 41% of the Kohl Park project area.

The current degraded habitat conditions have been partially caused by historical impacts from farming and the “land improvement” that typically went along with early agriculture (e.g., removal of forest cover and installation of drainage ditches). These impacts were compounded by illegal dumping, the spread of invasive plant species used as landscaping on adjacent properties, the installation of utilities, and significant erosion caused by discharge from a stormwater pond on an adjacent landowner’s property. Wetland habitat at Kohl Park is similarly degraded due to historic draining and filling of wetlands, modifications to the site’s topography, increased stormwater run-off from adjacent private properties, and declining water quality from leased agricultural fields (row-crops) at the site.

All current plant communities, and invasive species distributions are laid out in the floristic reference maps (Appendix Figures 9, 10, 11, 20, 21, 22). Flora inventories conducted by MCP staff combined with historic inventories conducted by SEWRPC have documented the presence of 366 species of plants at Kohl Park. Of these species, 243 are native although some are native to adjacent states but not historically Wisconsin, 104 are non-native, and of the non-native species 53 are listed by the WI DNR (NR40) as invasive species or are considered invasive species by the MCP. Common buckthorn is by far the dominant invasive species, with the other species predominantly found in smaller populations.

Southern Mesic Forest Existing SMF is found in MUs 2,3, 4, 7, and 10.

As with most urban natural areas, existing conditions are unique. The remnant western most SMF (MU10) (Appendix Figure 2) has a relatively closed canopy made up of mature sugar maple, red oak, young even-aged American basswood, boxelder, American elm, and swamp white oak with a handful of cottonwood and bur oak along the forest edges. SMF (MU10) lacks the native plant understory of the eastern SMF, which makes sense given its higher level of historic degradation. The eastern SMF (MU2) (Appendix Figure 2) has a large ephemeral pond with a slightly different mix of species including silver maple, cottonwood, American beech, American basswood, red oak, bur oak, and quaking aspen. Fortunately, the park had a low density of green ash which limited canopy loss from emerald ash borer (EAB).

Currently, the wetter woodlands are predominantly silver maple and bur oak with lesser populations of red maple, swamp white oak, American elm, cottonwood, willows, and box elder.

There are no historic SMF vegetation surveys for Kohl Park, but recent flora surveys conducted by MCP staff and SEWRPC have documented the presence of 106 native SMF plant species, of which 75% are species that MCP considers floristic species of conservation need within the greater MCP System. These are native species that have a coefficient of conservatism rating ranging from 5-10, indicating they are less tolerant to disturbed/degraded sites. Coefficient of Conservatism rankings are a method that assigns a number from 0-10 to each native plant species based on that species’ tolerance for disturbance and fidelity to a particular pre-European colonization plant community. In addition, these plant surveys suggest that the existing native assortment of the SMF tree canopies are currently 18 species. Despite the abundance of native species, the SMF at Kohl Park also contains 29 non-native plant species that are considered invasive species by MCP.

Focal species groups that have been documented utilizing the SMF at Kohl Park include forest breeding birds, crayfish and frogs. This list is further broken out in the Restoration Actions for SMF section below and the Focal Species Evaluation Matrix.

Grassland and Shrub-Carr Existing Grassland and Shrub-Carr habitats are found in MUs 1, 5, 6, 8, and 9.

The surrogate grassland and shrub-carr areas at Kohl Park have high levels of invasive species.

Populations of common buckthorn are particularly prevalent and have heavily invaded the grasslands units (exception being the planted prairie) and shrub-carr MU6. At this point, all the existing grasslands at Kohl Park is classified as surrogate grasslands or as “degraded” areas due to the presence of invasive species.

There are pockets of surrogate grassland consisting of non-native cool season grasses with more aggressive native forbs (e.g., goldenrod and aster species). The areas recommended for grassland planting and management (MUs 1, 5, and 9) at Kohl Park would have been SMF according to the surveyor maps from 1836. It could be argued that these areas should also be reforested, but there are several factors working against that recommendation. First, the soil structure has been severely compromised due to past farming practices (loss of topsoil); there is clear damage to soil structure from compaction (areas of unexpected seasonal wetness and patchy vegetative ground coverage), hydrological impacts (gully erosion and rapid run-off), and possible deposition of fill material (steep non-typical grade changes). The location of these historic impacts corresponds to the current locations of the surrogate grassland and buckthorn thickets at the site. Secondly, even pioneering/aggressive species of native trees have not established well in these grassland areas, which have been left idle for the past 40 years. This strongly indicates poor growing conditions for native trees

The shrub-carr wetland areas (MUs 6 and 8) east of 76th Street are small in size and structurally similar to the surrogate grassland areas at Kohl, containing pockets of herbaceous grassland/sedge meadow species. So, the decision was made to combine it with the grassland management component of this plan because most restoration techniques will be similar. The shrub-carr does contain ephemeral wetlands that typically persist into mid-summer. Odonate surveys conducted by MCP staff in 2024 documented one state listed species using these wetlands. The majority of this area is dominated by invasive species, especially common buckthorn and non-native grasses. The highest quality component is on the very south end of MU6. While MU8 along County Line Road is predominantly sandbar willow and non-native cattail.

Other adjacent areas of upland shrubs, shrub-carr, and degraded vegetation have an unusual mixture of native and non-native species growing together and creating a “novel” plant community. MCP defines a novel plant community as new combinations of species that arise spontaneously and irreversibly in response to anthropogenic land-use changes, species introductions, and extreme weather events, without correspondence to any historic ecosystem.

These plant communities, whether planted intentionally or coalescing independently with time, typically consist of a combination of aggressive native plant species, colonizing non-native/non-invasive plants, and aggressive invasive species. This plant community thrives in areas of historic disturbance where the original native plant community was extirpated from the site.

Historic vegetation surveys conducted by SEWRPC along with recent surveys by MCP staff have documented the presence of 121 native grassland/shrub-carr plant species, of which (36%) are species that MCP considers floristic species of conservation need. However, most of those species were found in the planted prairie, and did not naturally occur at Kohl Park. Regardless, these are native species that have a WI coefficient of conservatism rating ranging from 5-10 which are species with less tolerance to disturbed/degraded sites. However, the surrogate grassland and shrub-carr management units also contain 67 non-native plant species that are considered invasive species by MCP, and there are another 53 species (ex. red clover, alfalfa, timothy, etc.) that are non-native but not invasive either and are currently providing some habitat value to wildlife using the surrogate grassland and shrub-carr management units.

Miscellaneous surveys have also shown long-standing anthropogenic changes to the site which includes approximately 1,418 feet of drainage ditches in shrub-carr MU6, a half-acre former home site, and two large gullies (west - ~550 ft in length and east - ~744 feet in length) within grassland MU9. The gullies have been generated by water discharge from the “stormwater pond” on private property to the south of this management unit. In addition, multiple utility corridors and their corresponding easements limit what type of vegetation can be planted over and under these utilities. For example, a buried gas-line easement prevents tree planting in grassland MU5 and is the direct reason for the odd linear shape of that unit. (Appendix Figure 25). Encroachment from private properties (16 adjacent properties) is also evident with yard expansion along the southern boundary of MU9 and will need to be addressed before the restoration process can begin in that unit.

Focal species groups that have been documented utilizing the grasslands and shrub-carr at Kohl Park include breeding birds, crayfish, frogs, snakes and mammals. This list is further broken out in the Restoration Actions for Grassland and Shrub-Carr section below and the Focal Species Evaluation Matrix

Conifer Plantation The existing conifer plantation at Kohl Park is found in MU11.

The soil structure in the conifer plantation has been severely compromised due to past farming practices (loss of topsoil) and clear damage to the soil structure from compaction is visible in areas of unexpected seasonal wetness. Ozaukee Silt Loam, the dominant soil type in the conifer plantation, is not a wet soil and depth to the water table is typically 24-40 inches; however, moist soil conditions were evident during multiple seasonal field visits in 2024-2025. As a result, it is not advisable to return this habitat to the historic SMF.

Within this 25.7-acre management area, the conifers failed to establish in 6.8-acres in the north central part of the historic planting. Most of the tree failure corresponds with a seasonal drainageway and/or seasonally moist soil areas. The soils were likely too wet for the conifer species that were planted which were predominantly Norway spruce, white spruce, and Scotch pine. The few balsam firs, a wet soil species, in the plantation are not in the best of health, which is more likely due to being planted too far south of their natural range. In addition to the conifers, a few pioneering/aggressive species of native trees/shrubs (e.g., silver maple and gray dogwood) have established in areas where the original conifer planting did not take. Unfortunately, common buckthorn has also spread aggressively into those areas as well. Common buckthorn has also spread into the sub-canopy of the Scotch pine component of the planting because the pines have self-pruned their lower branches whereas the spruces have not. The white spruce and balsam fir lack resiliency to environmental changes, making them susceptible to loss over time, although both are minor components of the canopy. The Norway spruce will likely persist because they are found much farther south in the Midwest. The Scotch pine might be stressed and more prone to disease and insect damage, but they’ll likely persist for some time as well because they are an aggressive species. Recent (2021-2024) vegetation surveys by MCP staff have documented limited plant variety within the conifer plantation, which is to be expected given the habitat type and historic agricultural practices.

Despite consisting primarily of non-native species, the conifer plantation provides a unique habitat type in the AOC and the larger MCP park system. Dense stands of conifers are important areas of “thermal cover” for wildlife during inclement weather conditions. In general, thermal cover can be defined as areas where conifer trees, such as pines and spruces, provide shelter and warmth for wildlife during cold weather. These trees absorb and retain heat from the sun, creating a warmer micro-environment that helps animals maintain their body temperature during harsh weather conditions.

Given current site characteristics, conversion of non-conifer areas in this management unit to wet-mesic hardwoods and shrubs should be considered. Wet soil species typically have a faster growth rate than drier soil species, and canopy closure will help eliminate the growing conditions (full sun to partial shade) that are currently benefiting the establishment and persistence of common buckthorn. The potential seedling establishment from these native species will also help fill in the new canopy gaps in the conifers as they decline over time.

A segment of the MCP Forked Aster Hiking Trail (3,500 linear feet) runs through this management unit. The trail will need to be avoided during restoration activities, with any ruts being repaired and debris being removed from the footprint of the trail.

Focal species groups that have been documented utilizing the conifer plantation at Kohl Park include breeding birds, crayfish and frogs. This list is further broken out in the Restoration Actions for conifer section below and the Focal Species Evaluation Matrix

MCP Plant Database Throughout the ERMP development, MCP utilized their internal plant database, which catalogs the ~10,000 acres of natural areas within the park system. For example, a reference site for the existing SMF can be reviewed on a finer scale, and review what other SMF species exist park system-wide that may currently be completely absent from Kohl Park. This larger database shows an additional 96 native plant species that could have been historically present within the SMF at Kohl Park based on their presence in other SMF remnants within the park system. Reintroducing a portion of those missing plant species will work toward the goal of stabilizing and expanding populations of focal species at Kohl Park. Filtering this valuable plant information to develop a recommended planting list for the short and long-term ecological restoration of the SMF at Kohl Park requires assessing multiple factors such as:

• Removing species from the planting list that are currently not viable choices (ex: ash species)

• Removing species that are not available commercially (ex: most orchids)

• Removing species that occur in such small populations county-wide that large-scale seed collection is not a viable option (ex: Large-leaved shinleaf)

• Removing aggressive native species that may overwhelm restoration areas (ex: riverbank grape)

Ultimately this filtering provides a list of potential canopy species, understory species, and herbaceous species to choose from when restoring the plant community within the SMF and shrub-carr (Tables 2, 3, 4) at Kohl Park. This database was not utilized to develop a grassland/prairie plan as there is no naturally occurring mesic prairie within the Parks system.

Some of these species are included as potential species that are adapted to future growing conditions, as well as existing conditions. Planting locations need to consider matching the potential species to the on-site soil moisture conditions. The final planting plan and planting list for the HRP will be determined by the design consultant and can utilize the list plant lists developed in the ERMP phase, as seen fit by consultant.

Restoration Potential Overview With careful planning and proper placement, there are a number of ecological restoration actions that can be undertaken at Kohl Park such as: forest stand improvement, grassland and shrubland restoration and management, intensive invasive species management, reforestation, prairie establishment, and wetland enhancements. These actions can significantly improve available habitat for focal species at Kohl Park by creating a mosaic of habitat types for a variety of breeding and migratory species at the upper end of the AOC. Another consideration for the management actions as determined in the ERMP, are to make sure that this property can be properly maintained by MCP Natural Areas staff in the future.

The proposed strategy is reflected in the restoration actions below, which provide meaningful and achievable restoration activities which are then further broken down by habitat community type.

Restoration Actions Many of the following broad sitewide restoration actions were chosen for the benefit it will have on one or more focal species groups. These actions are suggestions provided by MCP Natural Areas staff and may be added to, altered, or removed to provide the best outcome for focal species, during Habitat Restoration Plan (HRP) development. Additional information on how these actions will impact Focal Species can be found in the Focal Species Evaluation Matrix (Appendix Table 5).

1. Manage existing areas of grassland and areas of prairie/sedge meadow species through select woody vegetation removal within invasive species removal locations. (MU 1, 3, 5, 6, 8, 9). Establish additional grassland areas (MU9) by planting the agricultural fields to mesic prairie (MU5),

2. Restore the remnant SMF and hardwood swamp through forest stand improvement to encourage a varied canopy assemblage, plant additional species of trees/shrubs/forbs in the understory and within canopy gaps and remove invasive species from the understory. Reforest “degraded areas” between isolated SMFs west of 76th Street to restore connectivity. (MUs 2 ,3 ,4 ,7 ,10). Reforest the agricultural field and the majority of the “degraded areas” east of 76th Street to SMF. (MU9)

3. Maintain conifer plantation by selectively removing invasive species and filling in canopy gaps. (MU11)

4. Targeted control and removal of invasive species that the MCP considers “priority” species (Appendix Table 6) throughout Kohl Park because they are not yet common within the Park System, and invasive species that are having a significant negative impact on the overall ecology of Kohl Park.

5. Assess the viability of filling in the drainage ditches east of 76th Street to restore hydrology allowing the expansion of the existing shrub-carr sedge meadow complex to the north (Figure 25).

6. Install artificial nesting structures (i.e., wood duck/merganser boxes, American kestrel boxes, songbird boxes, etc.) and modify the existing concrete silo to provide nesting habitat for chimney swifts. (MU10)

7. Develop an engineered plan to deal with the run-off coming from the stormwater pond on adjacent private property that is currently cutting large gullies through Kohl Park. (MU9)

Habitat Community Types Restoration Southern Mesic Forest Restoration and Expansion Overview:

Currently, SMF makes up 13.1-acres of the project area and has the potential to play an important role in providing meaningful and maintainable habitat at Kohl Park for Focal Species and many other wildlife species. By strengthening the ecological integrity of the remnant SMF and then buffering it with reforestation in the areas currently listed as “degraded”, there is the opportunity to expand the forest from the current 13-acres to 109.4 acres. There are few opportunities within the AOC to create/manage a contiguous forest of this size. Focal species that rely on forest habitat will directly benefit from the long-term impacts that a mature forest canopy can provide.

This includes increased breeding habitat, higher quality resources (food, water), and a larger patch size to house a greater number of species overall.

Deciding Process for SMF Restoration Action Goals The focal species that will potentially benefit from the Kohl Park SMF habitat restoration project (reforestation, increasing native plant species populations, and invasive species removal) are listed in the Focal Species Matrix (Appendix Table 5) and include forest breeding birds, crayfish and frogs.

Similar high quality SMF reference sites within the larger park system can be used in the development habitat restoration actions/goals for the Kohl Park SMF remnants. Additionally, the existing SMF in MU2 provides the best example within the boundaries of Kohl Park. The SMF in MU2 is floristically varied, it is also quite small and does not provide a full picture of the potential floristic potential of a SMF.

The small size and historic disturbance make it prone to numerous ecological threats such as:

• Introduction and spread of invasive species due to a high edge to core/interior ratio

• Large scale canopy loss and lack of native plant assortment from historic logging, conversion to agriculture, insects damage (e.g., EAB), and grazing

• Population fragmentation resulting in reduced adaptive capacity in native flora and fauna populations – the eastern SMF (MU2) is 1.2 miles from the western SMF (MU10), separated by development, invasive species thickets, agricultural land, and grasslands

One of the best ways to benefit focal species is to build in defenses against new and emerging ecological threats. In the SMF a healthy and expansive tree canopy can reduce populations of invasive species that thrive in full sunlight, assist with soil moisture retention (shading and duff layer), and provide seasonal food resources for wildlife. The reality of abrupt seasonal changes, invasive species, and emerging tree diseases means the forest canopy of 250 years ago will not be the forest canopy of 100 or even 50 years from now. This means while it is recommended to retain the previously mentioned SMF canopy species, there is also a need to integrate native tree species that have a slightly more southern natural range in the Midwest. As canopy gaps are reforested and the size of the SMF can be expanded through active reforestation, species such as hackberry, American sycamore, Kentucky coffee tree, tulip poplar, northern catalpa, etc. will bolster historic tree populations. These species of trees will offer habitat, nesting areas, and food sources (i.e. berries) for a variety of focal species including those in the mammals and breeding bird groups. To enhance forest resiliency, the plan recommends a minimum goal of 30 species of canopy trees for the SMF portion of the site, and the degraded areas recommended for reforestation. Canopy tree plantings in the existing woodlands may focus on areas of invasive species removal and in areas where canopy trees are declining or have recently died, therefore creating a canopy gap.

To further assess the existing canopy conditions and determine the locations of projected future canopy gaps, MCP staff geo-located and recorded all SMF canopy trees with a diameter at breast height (DBH) of 6” or greater within the Kohl Park remnant SMF focus area (Appendix Figures 9 and 20). However, specific tree species were excluded such as box elder, non-native species, and declining ash trees. This was done because those species are either weedy short-lived native species that will not contribute to long-term canopy closure, are invasive species that are recommended for removal, or are natives with current chronic disease or insect mortality challenges. It is important to note that short lived native canopy species do have an ecological role to play by stabilizing soils, providing cavity trees for wildlife, and they often prepare the woodlands for more conservative longer-lived species. This plan does not advocate for the removal of these short-lived natives unless absolutely necessary. Instead, it indicates the need to anticipate the decline of these species by planting other long-lived canopy species in the vicinity of short-lived native tree species. The canopy mapping allows the visualization of canopy stocking rates and present species within the existing SMF. Ultimately this allows for the assessment of whether any one species is too dominant or if long-lived canopy species are lacking. If so, a greater selection of canopy species can be planted in select areas to prevent future canopy loss, through mass die-offs in the manner that ash tree populations were eliminated by EAB, or to retain canopy closure as short-lived species decline and invasive tree species are removed.

An intact overstory is only one component of a healthy forest. Based on the larger park system plant database, there are a total of 40 species of native shrubs and small trees available to plant in the understory of existing canopy at Kohl Park. Fortunately, the majority of these species will also provide essential floral resources for pollinators and food resources (berries/nuts) for birds and small mammals at Kohl Park.

The final vegetative layer, the herbaceous layer, plays an important role preventing soil erosion, providing food resources to wildlife, and suppressing the invasion and spread of invasive species.

Fortunately, the plant list provides 139 species of herbaceous plants that could potentially be planted during the restoration process within the SMF restoration at Kohl Park.