Extension News

Preparing for Emerald Ash Borer in Iowa

Adult emerald ash borer

Note to media editors: This is the Garden Column for the week of March 30, 2007.


By Mark Shour


Iowa State University Extension


Iowans know how to respond to severe weather. If it is a tornado heading for their community, they head for their shelter that is prepared with a battery-powered weather radio, auxiliary lighting, water and food. If it is a life-threatening winter storm, they stay off the roads, check the readiness of their auxiliary power generator, gather blankets and other items to ride out the weather. We are survivors in this state!


Similarly, Iowans know how to respond to pests that threaten agricultural concerns. Whether it is soybean aphids, western bean cutworms, Asian soybean rust, Japanese beetles or another pest on the horizon, Iowans respond. Information is gathered from reliable sources, such as Iowa State University (ISU) Extension, time is made to attend classes, advice is sought from trusted crop advisors, the information is processed and the production plan is modified as needed.


For four years, ISU Extension has been conducting various outreach opportunities to alert Iowans of a destructive, exotic insect pest that has killed an estimated 25 million ash trees in the Midwest. The emerald ash borer, Agrilus planipennis, has made its way into Kane and Cook counties in Illinois, just a few hours away from our eastern border.


Thankfully, surveillance activities in Iowa during 2006 did not find emerald ash borer.  [For more information about these results, look at the spring 2007 issue of the Iowa Horticulturist magazine at http://www.iowahort.org/.]


You Can Help

Again, Iowans are called upon to step up to this challenge and work together to minimize the impact of this invasive pest. Some suggestions to assist in looking for the emerald ash borer are:

  • DETERMINE if you have an ash tree on your property. A user-friendly, pictorial key is available at www.extension.iastate.edu/pages/tree/, or take a few leaves on a twig to the nearest ISU Extension office or to an Iowa Department of Natural Resources district forester.
  • VOLUNTEER to help your community develop a tree inventory.  Knowing the type and location of tree species is important in responding to invasive pests.
  • PROTECT your trees from mechanical injuries (lawn mowers, string trimmers, construction projects, and vehicle parking on root zone). Insect borers seem to prefer as hosts trees that are stressed or damaged.
  • WATER trees during dry periods. For more information see: www.extension.iastate.edu/newsrel/2003/may03/may0318.html
  • KNOW the signs and symptoms of emerald ash borer activity:
    • thinning and dieback of branches in the crown.
    • epicormic shoots (water sprouts) produced directly below borer activity.
    • “D-shaped” exit holes in the bark.
    • woodpecker activity on trees, leaving light patches on the bark.
    • flattened, white larvae found feeding under the bark of ash trees and producing characteristic “S-shaped” tunnels.
      • dark, metallic, emerald green beetles seen on tree trunks or flying near ash trees. Adults are small, about as long as Mr. Lincoln’s image on a penny.
  • REPORT suspected sightings of emerald ash borer adults or symptomatic trees to the State Entomologist’s office (515) 725-1470, ISU Extension Entomology (515) 294-1101, or the Iowa Department of Natural Resources Forestry (515) 281-5918. 
  • REPORT any suspicious contacts with persons trying to sell you a guaranteed protection spray or injection of your ash tree to the Iowa Attorney General’s Office.  Also report any persons claiming you must remove your ash trees because of a “bug” in the area.
  • ENCOURAGE relatives and friends to buy local firewood, whether this is for heating, camping or hunting. The most likely way that emerald ash borer will come to Iowa is in firewood brought from infested states (Michigan, Indiana, Illinois or Ohio ).
  • TALK with city managers, county governmental officials, state legislators and U.S. congressional members.  Ask if they are aware of the threat this pest is posing to Iowa.  Have them watch an informational program to help them prepare for the emerald ash borer www.extension.iastate.edu/webcast/. Ask if they will help to establish adequate resources to contain/eradicate this pest when it is found in the state.
  • BOOKMARK your Web browser and keep up with current information in Iowa [/pme/home/pests/EAB.php] or from Michigan, Indiana, Illinois and Ohio [http://www.emeraldashborer.info/].


2007 Efforts Planned

The plan for 2007 includes revisiting sawmills and wood product sites (USDA Plant Protection Quarantine), inspecting ornamental plant nursery operations (Iowa Department of Agriculture and Land Stewardship), but the emphasis will be conducting visual surveys (ISU Extension Entomology) in federal, state, county and private campgrounds in Iowa. Approximately 200 trap trees will again be established, but sites will extend across the state, following major highways. 


Campgrounds are considered the highest risk sites in the state because the emerald ash borer moves long distance in firewood. The effort also will include using 100 experimental attractant traps, on loan from the USDA.



Contacts :

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

Jean McGuire, Extension Communications and Marketing, (515) 294-7033, jmcguire@iastate.edu

There are three photos for this week's column.


EABAdult3-30-07.jpg caption:  "Adult borers are dark, metallic, emerald green beetles usually found on or near ash trees." 


EABLarva3-30-07.jpg caption:  "The flattened and white emerald ash borer larvae are found feeding under the bark of ash trees and producing characteristic “S-shaped” tunnels."


EABFPS3-30-07.jpg caption: "Mark Shour, ISU Extension Entomologist, visiting with an Iowa citizen about emerald ash borer. Image by Keven Arrowsmith, ISU Extension Communications."