Forest inventory data estimates that Iowa's woodlands have over 52 million ash trees. Ash trees play an extremely important role in forest ecosystem function and health in Iowa. Many woodland owners have contacted the DNR with concerns about whether they should be harvesting ash before EAB arrives in the area.
Here are the current management recommendations:
- Until EAB is found in the area, continue regular forest management and scheduled harvests.
- In stands where ash forms 20% or more of the basal area, reduce the ash component during regularly scheduled thinning or harvesting.
- When selecting ash trees to thin, first remove those that have low vigor and quality and maintain dominant and co-dominant ash trees with good form/health for future harvests.
- When replanting or direct seeding, promote species other than ash. The goal should not be to eliminate ash, but to try to keep ash to 10% or less of all regeneration.
- As always, contact your local district forester for assistance in developing a management plan for your woodlands.
Research from EAB infested states has shown that all ash trees are susceptible to EAB regardless of the ash density, ash basal area, and ash health. Research data from Michigan found that most woodland's lost 98% of its ash population within the first six years of the first find of EAB on that stand. Progress in slowing EAB is currently being made by utilizing parasitic wasp (tiny wasp that kill EAB), ash phloem reduction (maintaining less than 10% ash in your woodlands), and trap trees to capture and destroy EAB larvae before they emerge (S.L.A.M.).