Is it Too Late to Save Your Ash Trees?
By now you have probably heard of the Emerald Ash Borer (EAB) and the devastation this tiny pest can cause to ash trees. Few things in life are guaranteed, but 100% of untreated ash trees WILL die! Dead ash trees become brittle and are dangerous when left standing.
Are my trees ash trees?
Leaves are compound and typically composed of 5 – 7 leaflets. Leaflet margins may be smooth or toothed. Leaflets are symmetrically arranged directly across from one another. On mature trees, the bark is tight with a distinct pattern of diamond-shaped ridges. On young trees, bark is relatively smooth.
Are my ash trees infested?
You may never see the actual insect because they are so small. Signs of infestation include: woodpecker damage (they peck off slices of bark to get at the larvae); tiny D-shaped exit holes after the adults emerge (difficult to spot); and general die-back of branches, usually beginning at the top of the tree.
The adult borer emerges in May to feed on leaves for a couple weeks, mate and lay eggs in the ash tree bark. The eggs soon hatch into the larval stage. The larvae eat the vital cambium vascular system of the tree just under the bark until early fall when they go into hibernation. Their tunneling disrupts the flow of water and nutrients to the tree, causing it to die within 2-3 years of infestation.
Can my trees be saved?
Critical to survival of the tree is the percent of the leaf canopy remaining. With early infestation (less than 25%), the soil drench method can control EAB when properly applied. Products are available to homeowners at home & garden stores. It is important to note that the soil drench pesticide is unsuitable for lakefront trees where run-off might occur.
An absolute minimum of 50% remaining canopy (preferable 60%) is the threshold of survival. With this level of degradation, the only pesticide to consider is the more effective TreeAGE direct trunk injection method, applied by a professional.
Should I treat my trees?
Consider the tree’s position in your landscape and value to your property. Treatment can be costly, but it may be worth it to save a good specimen in an ideal location in your yard. With the trunk injection method, the tree is protected for at least 2, possibly 3 years. Eventually, the population of EAB should drop significantly as all the untreated ash trees will be dead and they will not have anything to eat. For more information: https://extension.entm.purdue.edu/EAB/
What steps should I take?
As a property owner with ash trees, it is your responsibility to ensure that they are either treated or removed to protect your property and your neighbors’.
- Identify the ash trees on your property.
- Assess the level of infestation.
- Determine whether treatment is feasible or worthwhile.
- Have dying ash trees professionally removed before they become dangerous.