Emerald Ash Borer (EAB) is a serious threat to Maryland ash trees. It has killed many millions of ash trees across the Mid-West and Eastern U.S and is well-established in Maryland. The Maryland Department of Agriculture needs your help in locating possible infested ash trees and stopping the movement of the emerald ash borer into other areas. Even though all of Maryland west of the Chesapeake Bay is under quarantine, the infestations are spotty, so it is still very important to report possible infestations.  The Maryland Department of Agriculture will continue monitoring for this pest with the purple traps.  Adult beetles begin flying about the time that black locust is in bloom.

The EAB is an invasive pest from Asia that feeds on and kills ash trees.  EAB will kill even large ash trees within three years after infestation.  Ash trees are one of the most common and important landscaping trees used in Maryland and are common in western Maryland forests. Ash wood is used for all traditional applications of hardwood from flooring and cabinets to baseball bats. 

Presence of the emerald ash borer typically goes undetected until trees show symptoms of being infested – usually the upper third of a tree will thin and then die back. This is usually followed by a large number of shoots or branches arising below the dead portions of the trunk. Other symptoms of infestation include: small D-shaped exit holes in the bark where adults have emerged, vertical splits in the bark, and distinct serpentine-shaped tunnels beneath the bark in the cambium, where larvae effectively stop food and water movement in the tree, starving it to death.

If you have ash trees that you want to protect from EAB, treatments will need to be made in March.  Large specimen trees will need to be treated by a certified arborist. Consult the North Central IPM Center's fact sheet  for options, "Insecticide Options for Protecting Ash Trees from Emerald Ash Borer". Be sure to check labels and instructions to make sure that Emerald Ash Borer is on the label.  To help you make a decision on treatment, Purdue University published an excellent decision guide.

To help stop this damaging beetle, homeowners and citizens who live in and travel through known infested areas can help.

• Don’t move firewood – buy it where you burn it.  Hauling firewood is the most common way for damaging plant pests to be moved from one area to another.
• Don’t plant ash trees.  As the EAB is expanding its range in Maryland, diversified plantings of alternative tree species are recommended for residential landscaping.
• The USDA expanded the federal quarantine to include all areas where EAB is under state quarantine under a federal quarantine area. Current quarantine information for other states can be found here at emeraldashborer.info where is EAB.
• Maryland west of the Bay is under quarantine.  Ash plant material, products, and firewood are prohibited from movement to the Eastern Shore.
• Report any signs of the emerald ash borer to the University of Maryland Home and Garden Information Center at 1-800-342-2507. 

Click here for additional information about the emerald ash borer. For information about the MD quarantine visit the Maryland Department of Agriculture website, or call  410-841-5920 . The following is also a very informative website about EAB: www.stopthebeetle.info/

Excellent Links to Emerald Ash Borer Information

• Ash Tree Identification
• Main Emerald Ash Borer Information Page
• Maryland Department of Agriculture - EAB information
• Emerald Ash Borer Pest Alert - USDA Forest Service, Northeastern Area
• www.emeraldashborer.info - excellent multi-state site from Michigan, Indiana and Ohio
• Michigan Emerald Ash Borer site - Michigan Department of Agriculture
• Spanish language Emerald Ash Borer site- Purdue University
• Emerald Ash Borer Lookalike Chart - University of Nebraska
• 2nd Edition Insecticide Options for Protecting Ash Trees from Emerald Ash Borer
• Managing Emerald Ash Borer Decision Guide
• Frequently Asked Questions Regarding Potential Side Effects of Systemic Insecticides Used to Control EAB
• Hungry Pests
• Stop the Beetle

Report: If you suspect your ash tree is infested with EAB call HGIC and speak with a horticulture consultant or contact us through our website.