Management Goals & Treatments
A team of natural resource specialists from Colorado State University, the Mississippi Park Connection, Saint Paul Parks and Recreation, and local collaborators teamed up with regional scientists from the University of Minnesota and the Northern Institute of Applied Climate Science to participate in a two-day workshop in March 2019 to develop the ASCC treatments for the first urban affiliate site at Crosby Farm Regional Park. The team developed a set of management objectives, desired future conditions, and silvicultural tactics for each adaptation option:
Management Goals:
Maintain a closed canopy condition
Maintain the current species composition in the tree canopy and regeneration layer of the floodplain forest ash-elm species
Promote or enhance native regeneration
Manage to decrease invasive species cover (trees and herbaceous layer)
Maintain large diameter trees while creating a range of diameter classes for wildlife habitat
Maintain vigor of existing desirable trees
Maintain recreation value and opportunities for multiple use of the area
Strive for an educated and engaged public
Strategies & Approaches:
Site prep for natural regeneration and planting
Scout, treat, and remove invasive plant populations
Create gaps for regeneration using the following prioritization:
Utilize natural gaps (dying ash pockets/cottonwood gaps) for regeneration
Remove “hazard” trees from trails (hazard removal is the priority for all treatments including control/no action)
Create additional gaps for regeneration of desired species if natural gaps and hazard tree removal options do not provide enough opportunities for desired species regeneration
Maintain large diameter trees, particularly silver maple and cottonwood, as well as large-diameter standing dead for wildlife habitat and eagle nesting
Consider treating selected large ash
Plant under-represented species that currently grow on site: silver maple, hackberry, cottonwood, and Dutch-elm resistant American elm seedlings to help maintain the floodplain forest ash-elm cover type
Protect all regeneration from herbivory using deer exclosures around plantings
Allow natural flood deposition and use as microsites for planting future-adapted species
Use volunteers and increase visitation, education, and use of Crosby Farm Regional Park as a teaching forest
allow some change in current conditions, but encourage eventual return to original conditions
Management Goals:
Promote a broad suite of future climate-adapted species (flood-tolerant and drought-tolerant) native to the Mississippi River Basin
Promote less common native species
Promote trees with vigor and seed potential
Low herbivory
Low abundance of invasive species
Provide wildlife trees with big crowns and cavity trees or snags for nesting wildlife species
Maintain recreation value and opportunities for multiple use of the area
Strive for an educated and engaged public
Strategies & Approaches:
Site prep for natural regeneration and planting
Scout, treat, and remove invasive plant populations
Create gaps for regeneration around high-value, large-diameter seed trees using the following prioritization:
Utilize natural gaps (dying ash pockets/cottonwood gaps) for regeneration
Remove “hazard” trees from trails (hazard removal is the priority for all treatments incl. control/no action)
Create additional gaps for regeneration of desired species if natural gaps and hazard tree removal options do not provide enough opportunities for desired species regeneration
Create skips in areas where the canopy cover target is important
Plant species that are currently found onsite using a southern seed zone location (silver maple, hackberry, cottonwood, Dutch elm-resistant American elm, bur oak, black willow)
Plant species that may currently be offsite but within geographic range of the Mississippi River Basin (swamp white oak, river birch, peachleaf willow, red mulberry, Kentucky coffee tree)
Plant species on appropriate microsites, especially with respect to potential changes in flooding regime and hydrological changes with climate change
Protect all regeneration from herbivory using deer exclosures around plantings
Allow natural flood deposition and use as microsites for planting future-adapted species
Use volunteers and increase visitation, education, and use of Crosby Farm Regional Park as a teaching forest
actively facilitate change to encourage adaptive responses
Management Goals:
Promote a broad suite of future climate-adapted species (flood-tolerant and drought-tolerant) from seed zones farther south along the Mississippi
Create a diversity of canopy cover conditions over space and time that is heterogeneous for regeneration
Promote heterogeneous age classes and canopy structure
Maintain recreation value and opportunities for multiple use of the area
Strive for an educated and engaged public
Strategies & Approaches:
Site prep for natural regeneration and planting
Create gaps that are ideally 1 acre to 1.5 acre to accommodate selected species, avoiding river edges while creating a variety of microsites for species
expand gaps with feathered edges
girdle trees on edges
create microsites for planting
Plant containerized and bare-root stock of sycamore, honey locust, southern pin oak, swamp white oak, river birch in the gaps; and winged elm, red maple, red mulberry, northern catalpa along the edges
Treat invasives where they are impacting regeneration
Monitor for stressors and survival and adjust as needed (adaptive management)
Protect all regeneration from herbivory (deer and beaver) using deer exclosures around plantings, but also consider alternative options of fencing, repellent, and seedling tubes
Retain large-diameter standing dead for wildlife habitat
Allow natural flood deposition and use as microsites for planting future-adapted species
Use volunteers and increase visitation, education, and use of Crosby Farm Regional Park as a teaching forest