Emerald ash borer crops up in two new counties

by | Jun 10, 2015 | News

DES MOINES, Iowa (IDALS) ? Emerald Ash Borer (EAB) has been positively identified in Davenport and central rural Davis County, bringing the total of confirmed counties to twenty-four since it was first detected in Iowa back in 2010. This metallic green insect which only measures about half-inch long and an eighth-inch wide kills all ash tree species and is considered to be one of the most destructive tree pests ever seen in North America.

?With emerald ash borer already being in the area on the Illinois side, it was only a matter of time until it was found in Davenport.? said Mike Kintner, Iowa Department of Agriculture and Land Stewardship EAB and gypsy moth coordinator. ?With these two newest findings being nearly one hundred miles apart, it is a good reminder that we just never know where or when this ash-killing insect is going to reveal itself.?

The City of Davenport?s Forestry Division has been planning for the arrival of this exotic pest and has a working Emerald Ash Borer Response Plan in place. The city plans to remove ash trees infested with EAB on public properties and continue to reduce its ash tree populations in public areas. The Davis County find was in a rural area north of Bloomfield, IA.

Out of the twenty-four Iowa counties that have confirmed EAB findings, six have been found this year alone. A statewide quarantine, issued in February 2014, remains in place, restricting the movement of hardwood firewood, ash logs, wood chips and ash tree nursery stock out of Iowa into non-quarantined areas of other states.

?We still strongly urge Iowans to not move firewood long distances,? said State Entomologist Robin Pruisner of the Iowa Department of Agriculture and Land Stewardship. ?A large portion of Iowa is not showing signs of EAB infestation; let?s keep those areas EAB-free as long as possible by not moving wood that potentially harbors EAB or other tree pests. Be vigilant and report suspicious symptoms in counties that are not yet known to be infested to a member of the Iowa EAB Team.?

The Iowa EAB Team provides EAB 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 Plant Health Inspection Service and the USDA Forest Service.

The Iowa EAB Team strongly cautions Iowans not to transport firewood across county or state lines, since the movement of firewood throughout Iowa or to other states poses the greatest threat to quickly spread EAB and other plant pests. Most EAB infestations in the United States have been started by people unknowingly moving infested firewood, nursery plants or sawmill logs. The adult beetle also can fly short distances, approximately 2 to 5 miles.

At this calendar date, the treatment window for soil-applied preventive treatment measures (soil injection, or soil drench, or granular application) has ended. Basal trunk sprays with dinotefuran can be applied until mid-June and are most effective for trees less than 18? dbh ? the diameter of the tree?s trunk at breast height, 4 ? feet above the ground. Trunk injection remains a viable EAB management option, as this method can be done when the tree has a full canopy of leaves (now through August), provided there is good ground moisture. 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, and treat during the recommended treatment time.