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Emerald Ash Borer Found In Logan, Menard, and Sangamon Counties
By John Fulton

[October 11, 2014]  With the presence of emerald ash borer confirmed in all three of our counties, the “What Next?” questions are coming in fast and furious. They rank only second to “Would you look at my ash tree?” As for looking at the ash trees, it is physically impossible to look at all of them. If you want to provide pictures or drop samples by, we can try and deal with requests in that manner. In the weeks ahead, most communities will roll out their control and containment plans because of the findings – so stay  tuned for further information.

Most communities have an abundance of the various ash trees, as they were frequently used as replacements for the American Elm trees afflicted by Dutch Elm Disease. To answer the other question, Jennifer Fishburn, University of Illinois Extension Horticulture Educator in the Logan, Menard, and Sangamon Unit, has provided the following information:

The Illinois Department of Agriculture announced on October 6, 2014 that emerald ash borer had been identified in several counties including Logan, Menard and Sangamon counties.

This destructive, non-native pest feeds on North American ash species (Fraxinus sp.). This includes white ash, green ash, black ash and blue ash trees. In Illinois white and green ash are the most commons species. This does not include mountain ash which is not a true ash. Emerald ash borer attacks both healthy and stressed ash trees.

Ash tree can be identified by opposite, pinnately compound leaves. A leaf has 5 to 9 glossy, dark green leaflets. Young bark of ash trees is usually flaky. Mature trees have light-gray to gray-brown bark, with ridges and deep furrows forming diamond-shaped areas. For information on “Ash Tree Identification,” view handout from Michigan State University Extension,http://www.emeraldash
borer.info/files/E2942.pdf

The beetle is native to Asia, and was first discovered in North America in southeastern Michigan in the summer of 2002. It seems that the pest arrived in Michigan via infested wood packaging material. Through hitchhiking on firewood, nursery stock and logs, Emerald Ash Borer infestations are now in Colorado, Georgia, the East coast and throughout the Midwest.

Signs of infestation include die-back beginning in the upper third of the tree and progressing downward, serpentine-shaped (or S-shaped) tunnels just beneath the bark, vertical splits in the bark and increased woodpecker activity. One-third to one-half of the branches may die in one year. Most of the canopy will be dead within two years of observed symptoms. Additional signs include the presence of the adult metallic-green beetles on or around ash trees, thinning and yellowing leaves, 1/8 inch diameter D-shaped holes (about the size of a BB) in the bark of the trunk or branches, and shoots growing from the base of the tree (epicormic shoots). Infested trees may not show physical signs of damage for four to six years.

 The emerald ash borer, Agrilus planipennis, adult is a small metallic-green beetle, about 3/8 to 5/8 inch long, and 1/8 inch wide. The adult feeds on ash foliage but causes little damage to the leaves.
Emerald ash borer larvae feed on the inner bark of ash trees. These tunnels cut off the flow of nutrients and water between the tree’s roots and canopy, thus starving the tree. The larvae are flat, legless, heavily fragmented, creamy white and reach about 1 inch in length.

If you have an ash tree, what now? Ash trees that are treated with insecticide can be saved, but before beginning treatment, consideration should be given to assessing the health and vigor of the tree.

Unhealthy trees with more than half of their leaves missing, lacking vigor, planted in a poor site, or having bark splits or water sprouts are not likely to respond well to treatments. Avoid treatment of trees showing more than 50 percent canopy decline; these ash trees are unlikely to recover even if treated.

Healthy trees showing vigorous growth, that enhance landscape value and showing few signs of decline are good candidates for treatment. University of Illinois recommends starting insecticide treatments when your tree is within 15 miles of an EAB infestation, or if you are within a county that is quarantined. For information on treatment options view “Insecticide Options for Protecting Ash Trees from Emerald Ash Borer” publication which can be found on the Emerald Ash Borer website at http://www.emeraldashborer
.info/files/Multistate_EAB_Insecticide_
Fact_Sheet.pdf

For information on proper identification of an ash tree, photos of the emerald ash borer and other problems of ash trees, visit the Emerald Ash Borer website, http://www.emeraldashborer.info 

[By JOHN FULTON, COUNTY EXTENSION DIRECTOR SERVING LOGAN, MENARD, AND SANGAMON COUNTIES]