Project Area
The Minneapolis Parks and Recreation Board’s forestry department plants, prunes and removes all trees on public property, including nearly 200,000 boulevard trees on 1,100 miles of streets, 400,000 park trees on more than 6,000 acres of land, and trees on other city properties, such as police and fire stations, stormwater retention ponds, and Public Works facilities.
Management Goals
The overall goal of this project is to ensure the Minneapolis public urban forest provides maximum benefits for current and future residents by being resilient to future conditions.
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Objective: Analyze Minneapolis Park & Recreation Board public tree planting selection guidelines for street trees to gauge opportunities to increase urban forest resiliency in preparation for future conditions at population, community, and site scales.
Climate Change Impacts
For this project, the most important anticipated climate change impacts include:
The Midwest is expected to experience between 5 and 30 more days per year with a maximum temperature exceeding 95 degrees Fahrenheit by the middle of the century which could stress certain trees and make establishment of new trees more difficult.
Increasing winter low temperatures might lead to a change in hardiness zones that would allow for more tree species diversity. It may also lead to increased pest pressure.
Increased precipitation could aid tree vigor and growth. It could especially help with new tree establishment.
The number of days per year with more than 1 inch of precipitation will increase across the Midwest by the middle of the century which could lead to localized flooding
Challenges and Opportunities
Climate change will present challenges and opportunities for accomplishing the management objectives of this project, including:
Challenges
Trees on challenging sites may need additional resources and care to establish and thrive.
Opportunities
Planned intentional diversity within selections of mostly "No Change" Tree Atlas projections bodes well for urban forest resilience.
Adaptation Actions
Project participants used the Adaptation Workbook to develop several adaptation actions for this project, including:
Area/Topic
Approach
Tactics
Continue to utilize existing street tree planting guidelines which prescribe diversity at multiple scales across the urban forest.
8.2. Favor existing genotypes that are better adapted to future conditions
8.3. Use new genotypes that are better adapted to future threats and conditions
8.3. Use new genotypes that are better adapted to future threats and conditions
Continue species and cultivar trials, especially with University of Minnesota partnership, to measure success of potential new or rarely used cultivars.
1.1. Maintain or restore soils and nutrient cycling in urban areas.
1.2. Maintain or restore hydrology
1.4. Reduce competition for moisture, nutrients, and light
1.2. Maintain or restore hydrology
1.4. Reduce competition for moisture, nutrients, and light
Identify challenging sites for tree establishment, then increase investment on these sites to aid establishment.
Monitoring
Project participants identified several monitoring items that could help inform future management, including:
Arborist and Forester compliance with tree planting guidelines.
Neighborhood scale: 10% genus restriction.
Block scale: 5 tree limit per genus & 5 tree limit per Asian Longhorned Beetle preferred host genera (Birch, Buckeye, Elm, Maple)
Two to Three annual check-ins/report cards to guide quality assurance. March, July, September
Project Documents
Keywords
Diseases
Genetic diversity
Insect pests
Planting
Urban