Remember those billboards that asked Marylanders to not move firewood? Have you noticed bright purple triangular shaped plastic traps hanging in ash trees? This is because the emerald ash borer plagues our state and some counties are under quarantine. Emerald ash borers can reside in cut hardwood and the purple traps help scientists determine if they are spreading.
This bright green insect kills trees by tunneling into the tree and because of this damage the tree will not get the nutrients it needs and die. First, the upper third may die, and shoots may begin to sprout on the lower part. The emerald ash borer leaves a network of tunnels under the bark. The insects also leave D shaped exit holes and the bark may split.
While this may seem like a problem for park rangers, we have plenty of ash trees here in Baltimore City. In fact, it is the most common tree in Baltimore. If you don’t have an ash tree in your yard there may still be some on your street or in your local park. According to the Maryland Department of Agriculture, ash trees make up about 10.4% of the total trees in Maryland.
The emerald ash borer came to America in 2002 and was thought to have arrived in packing materials for shipping. On June 8, 2011, this Asian beetle was found in Howard County. At that time, this area joined Prince George’s and Charles counties in quarantining this insect. Under these restrictions people may not move ash trees or any hardwood firewood out of the areas. Local arborists hung purple traps baited with Manuka tree oil, which mimics the smell of a damaged ash tree. The traps are purple because studies show that the emerald ash borer is attracted to the color.
Other than not moving firewood or planting new ash trees, Marylanders can report emerald ash borer sightings to the University of Maryland Home and Garden Information Center at 1-800-342-2507 or the Maryland Department of Agriculture at 410-841-5920. Here is a handy chart put out by the University of Nebraska. This PDF shows how the emerald ash borer is distinct from other insects that people mistake it for. The Maryland Home and Garden Information Center has a page with many photographs of the insects and ash tree damage.
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