Ash Tree Management Plan

Ramsey County Parks & Recreation created a management plan in response to the effects of emerald ash borer (EAB) on ash trees on county-managed land.

This plan includes a system-wide inventory and plan for ash tree removal and replacement within the department’s jurisdiction. This approach is more cost-effective and it allows for work to be done in phases. As of 2025, priority trees have been removed. Removals are ongoing for lower-priority ash, and will continue as funding allows.

Background

EAB is an insect that attacks and kills ash trees. They spread through short distance natural flight and infested firewood transported long distance. The adults are small, iridescent green beetles that live outside of trees during the summer months. The larvae are grub or worm-like and live underneath the bark of ash trees. Trees are killed when larvae tunnel under the tree's bark.

EAB was first discovered in the United States in 2002 near Detroit, Michigan. In May 2009, the first cases of EAB were found in Minnesota within Saint Paul. The city of Saint Paul and its surrounding suburbs began creating management plans shortly after. Many cities are now nearing ten years of planning and management.

EAB has widely infested ash trees within Ramsey County. In 2010, Parks & Recreation began taking inventory of ash trees throughout golf courses and recreational areas of the park system.

Ash tree management

The options for ash tree management include remove and replace, chemical treatment and biocontrol agents. Parks & Recreation has opted for removal and replacement, similar to many other counties and municipalities. 

Benefits of removal and replacement approach:

• Removal and replacement is shown to be the longest term, most cost-effective measure.
• It generally takes 3–5 years for an ash tree infected with EAB to die. Removing these trees before mortality occurs reduces the number of dead and potentially hazardous ash trees.
• Replanting with varying tree species increases resilience to future pests and pathogens.

Our response

With internal efforts combined with assistance from Tree Trust and other community partners, we have removed and replaced a significant amount of ash in the county.

Removal of ash has been completed within high priority areas, primarily parking lots and other trafficked spaces. The majority of these trees have been replaced, and are being cared for by community partners and park staff to replace the gaps in the urban canopy. To avoid future issues from invasive pests and pathogens, ash trees are being replaced with a range of species including American basswood, disease resistant elm, redbud, yellow wood, honey locust, coffee tree, planetree, pin oak, red oak, birch, swamp white oak and more. Ongoing maintenance of these trees includes watering, stabilizing and protecting trees as needed to ensure establishment.

Ash tree removal is ongoing within the county as funding allows. Currently, funds are not available to address trees on private land. Please contact us if you have a tree to report for suspected EAB infestation.