Emerald Ash Borer found in two more Iowa counties

The emerald ash borer has made its way into two more Iowa counties, bringing the total number of infested counties in the state to 45.

Fayette and Madison counties are the most recent to be added to the list.

Emerald Ash Borer is a destructive wood-boring beetle that attacks and kills all ash tree species. The exotic pest was first discovered in Iowa in 2010.

In Fayette County, the insect was discovered in an ash tree owned by the city of Oelwein. For Madison County, the finding took place in a rural area south of Winterset. Insect specimens taken from these sites were confirmed as ash borer by a federal identifier.

'This year, we have already had six new counties confirmed with (emerald ash borer),” said Mike Kintner, Iowa Department of Agriculture and Land Stewardship emerald ash borer and gypsy moth coordinator. 'I anticipate this number to only grow throughout 2017, passing last year's mark of 10 new county finds.”

The Iowa Emerald Ash Borer Team provides diagnostic assistance to landowners and includes officials from Iowa Department of Agriculture and Land Stewardship, Iowa State University Extension and Outreach, the Iowa Department of Natural Resources, USDA Animal and Plant Health Inspection Service and the USDA Forest Service. Anyone who suspects an infested ash tree in a county not known to have been infested is urged to contact one of these team members:

l Mike Kintner, (515) 745-2877, mike.kintner@IowaAgriculture.gov.

l Robin Pruisner, (515) 725-1470, robin.pruisner@IowaAgriculture.gov.

l Paul Tauke, (515) 725-8450, paul.tauke@dnr.iowa.gov.

l Tivon Feeley, (515) 725-8453, tivon.feeley@dnr.iowa.gov.

l Emma Hanigan, (515) 249-1732, emma.hanigan@dnr.iowa.gov.

l Jesse Randall, (515) 294-1168, randallj@iastate.edu.

l Mark Shour, (515) 294-5963, mshour@iastate.edu.

l Laura Jesse, (515) 294-0581, ljesse@iastate.edu.

l Donald Lewis, (515) 294-1101, drlewis@iastate.edu.

l Jeff Iles, (515) 294-3718, iles@iastate.edu.

The adult beetle is metallic green in color and measures approximately one-half inch long and can be noticed during the summer months. The larvae burrow through the inner layer of bark, eating away at the vascular tissue, which supplies nutrients to the tree. Starved trees usually die within two to four years.

Infested ash trees display canopy dieback beginning at the top of the tree and progressing downward, S-shaped feeding galleries under dead or splitting bark, D-shaped exit holes, water sprouts (along the trunk and main branches), and increased bark damage by woodpeckers.

If a landowner is interested in protecting a valuable and healthy ash tree within 15 miles of a known infestation, the treatment window for protecting an ash tree begins soon. Soil treatments should be made from mid-April to mid-May. Basal trunk sprays should be applied mid-May to mid-June. Trunk injections begin once the tree has a full canopy.

A federal quarantine, enforced by the U.S. Department of Agriculture, remains in effect and restricts the movement of all hardwood firewood and ash articles out of Iowa into non-quarantined areas of other states. To help reduce the potential for people to unknowingly transport EAB and other destructive tree-killing pests, Iowans are strongly encouraged to use locally sourced firewood.

For more information, including a full list of Iowa counties where emerald ash borer has been discovered, go to IowaTreePests.com.