Emerald Ash Borer confirmed in Marshall and Tama counties
A highly destructive beetle that targets and kills ash trees, the emerald ash borer (EAB), has been confirmed in Marshall and Tama counties.
The insect was found after a landowner noticed tell-tale woodpecker damage on his ash trees. After more investigation, EAB larvae from the trees were collected in a rural area north of Le Grand.
EAB is native to Asia and was first identified in the U.S. in 2002 and in Iowa in 2010 in Allamakee County. Much of the pests’ spread can be attributed to humans inadvertently transporting it to new areas under the bark of firewood, logs and tree debris.
Infected ash trees display canopy dieback, S-shaped feeding grooves beneath bark, D-shaped exit holes, water sprouts along the trunk and main branches and bark loss.
The one half inch beetle is a metallic green color and can be seen in the summer. Larvae burrow through the inner layers of bark. EAB-infected trees usually die between two to four years.
At this calendar date, the window for all preventive treatments has closed. If a landowner is interested in protecting a valuable and healthy ash tree within 15 miles of a known infestation, he or she should have landscape and tree service companies bid on work, review the bids this winter, and treat beginning spring 2018 (early April to mid-May).
Additional resources for information about Emerald Ash Borer are:
The Emerald Ash Borer Information:
The Department of Natural Resources:
The Iowa State University Extension Service: