Love your ash trees? Take steps to protect them from the Emerald Ash Borer
All ash trees in Montgomery County are at risk of long term damage or death caused by the Emerald Ash Borer (EAB). This beetle was brought to the United States from Asia and has spread across all of Maryland and surrounding states.
As adults, EAB do not cause significant damage to trees. However, their larvae threaten all species of ash trees by feeding on the tissue between the bark and wood.
Unless we are proactive in protecting ash trees from damage caused by EAB, scientists predict that nearly all ash trees in Montgomery County will die within the next 10 years.
Treatment is effective and treating ash trees in the early stages of EAB infestation can minimize damage, allow for recovery, and prolong their life.
Be Proactive in the Battle Against Emerald Ash Borers
Even if your ash trees do not have EAB now, you should expect EAB to infect your trees sometime over the next ten years. To save your ash trees, you must act before EAB arrives.
Seek the Advice of a Tree Expert
Due to the nature of EAB, we recommend everyone with ash trees seek the help of a tree expert.
- If your trees isn’t showing clear signs of EAB-related damage, advance treatment is the best way to protect the tree and prevent infection
- If your trees have an early stage EAB infection, treatment is the best way to save your tree.
- If your trees have an advance EAB infection or you have a dead tree, a tree expert will help you determine if your tree is hazardous and at risk of falling. You also want to prevent the EAB from spreading to other trees.
Long story short – if you have ash trees, seek the guidance of a tree expert as soon as possible!
Guide to Hiring an Expert
How do I identify ash trees?
Here are two fact sheets to help identify ash trees:
How can I identify if my ash trees already have EAB?
Ash trees infested with EAB rapidly become brittle and hazardous. These trees often become hazardous before they die. Watch this short video about how to identify ash trees and damage from EAB:
Note that you no longer need to report EAB to authorities because it’s now found everywhere in Maryland and surrounding states.
Remember: Don’t move firewood.
Buy your firewood locally. Moving wood products, especially firewood, increases the spread of invasive pests, like EAB and gypsy moths, that threaten the health and life of forests and trees. Learn more here.
How do EAB kill ash trees? Why are infested trees dangerous?
EAB larvae feed on the layers of cambium tissue between the bark and wood of ash trees. They bore tunnels while feeding on the cambium. This boring interrupts the flow of water and starch through each tree causing the leaves and branches to die.
The lack of water in the leaves and branches causes them to rapidly dry and become brittle. Once the crowns are dry, ash trees are hazardous and could fall or snap off at the base. Large dead branches could fall at any time, as well.
EAB typically feed from the top of ash trees down the branches to the stem. As such, visible signs of damage starts at the top of trees and spreads to the lower trunk. Therefore, if you can see the D-shaped exit holes made by EAB larvae at eye-level, then the tree is likely to be heavily infested.
It is important to contact a licensed tree expert as soon as ash trees are identified.
More information is available on the following websites:
- Emerald Ash Borer Information Network is a great place to collect general information about EAB.
- The Maryland Department of Agriculture offers a helpful Homeowners Guide .
- The US Forest Service includes detailed information in their page about the biology and the life cycle of EAB.
- Montgomery County Parks has general information about EAB in our local parks.