Issue 16, September 19, 2011

Emerald Ash Borer Recent Finds

Emerald ash borer (EAB) has been found recently in three Illinois counties that were not known to have the insect previously. They are Kankakee, Marion, and Effingham counties.

Kankakee county locations include Kankakee River State Park, Route 102 in Bourbonnais, and North Hobbie Avenue in Kankakee. All three finds were verified by USDA APHIS on July 19, 2011. Kankakee County is within the state quarantine established after EAB was found in Iroquois and Champaign counties last year. The beetle has also been found previously in Will County, so its occurrence in Kankakee County was expected.

The Marion County detection marks the first find of EAB in southern Illinois. It was discovered during the harvest of the purple sticky traps used in an EAB study by the U.S. and the Illinois Departments of Agriculture. The intensive 55-county study conducted by the federal and state departments of agriculture revealed EAB has taken up residence in ash trees just north of Salem Illinois. Illinois Department of Agriculture (IDA) staff collected several specimens from a single trap placed in a Marion County rural residential area situated about a mile east of I-57 and a mile north of US 50. USDA APHIS confirmed that is was EAB on August 25, 2011. Subsequent investigation of attacked trees in the area reveals that EAB has been at the Marion County location for an estimated five to seven years.

The Effingham County detection occurred when IDA officials were making a site visit to meet with Salem officials. IDA staff observed some unsightly ash trees at the Green Creek Rest Area on I-57, 4 miles north of Effingham in Effingham County en route and stopped to make an inspection where they found live larvae. USDA APHIS also confirmed this find as Agrilus planipennis, or EAB on September 13, 2011.

The Marion and Effingham County finds are outside of the current state quarantine for EAB. New quarantine boundary adjustments will not be made until all purple traps have been harvested and analyzed, but Marion and Effingham County residents are urged to heed all quarantine guidelines as if they were officially quarantined. Homeowners and others interested in EAB Management are encouraged to attend an upcoming seminar being hosted in Effingham County on Nov. 1 at the University of Illinois Extension office at 1209 Wenthe Drive in Effingham. The event will take place from 9am-2pm. To sign up for the seminar, contact the Extension office at 217-347-7773.

All of the finds of EAB in Illinois outside of the Chicago metropolitan area have been along or near interstates. IDA officials highly suspect that unwitting automobile, truck and train traffic may be culprits for the exacerbated transport of this pest. Less than 50 yards from the trap location near Salem in Marion County is a major freight rail line, a multiple rail line siding, and switching yard. Trains stop along there numerous times a day for up to an hour.

With these recent finds in southern Illinois, IDA officials strongly encourage a heightened awareness of stressed and weakened ash trees. Local and regional tree companies, villages, and cities should explore the Department of Agriculture's compliance agreement program, and generally brush up on rules and regulations pertaining to the processing and transport of ash materials.

Kankakee, Marion, and Effingham counties bring the total number of Illinois counties with a confirmed EAB infestation to twenty. Previous detections were made in Boone, Bureau, Champaign, Cook, DeKalb, DuPage, Grundy, Iroquois, Kane, Kendall, Lake, LaSalle, McHenry, McLean, Ogle, Will and Winnebago counties.

The emerald ash borer is difficult to detect, especially in newly-infested trees. Watch for metallic-green beetles about half the diameter of a penny on or near ash trees that are showing signs of disease or stress. Other signs of infestation in ash trees include D-shaped holes in the bark of the trunk or branches and shoots growing from its base. Since the emerald ash borer was first confirmed in the Midwest in the summer of 2002, more than 25 million ash trees have been felled by the beetle.

Emergence holes.

Anyone who suspects a tree has been infested is urged to contact either their county Extension office or village forester. For more information, visit IDA's website or the EAB information on the University of Illinois IPM website. (Phil Nixon and IDA News Release)

Phil Nixon

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