If you have a white ash tree in your yard, and it is dying, you may be able to save it if you know what the problem is. In some cases, however, there will be nothing you can do. Below are three diseases your tree may have, as well as how to care for your ash tree.
There are a variety of ash-tree diseases, and some of the most common you will find include the following.
Emerald Ash Borer
The emerald ash borer (EAB) is a wood-boring beetle that feeds on the foliage of the ash tree. The larvae from the adult beetles feed on the inner bark, and this makes it much harder for the tree to transport nutrients and water. Over time, this will kill your ash tree.
If your ash tree has EAB, you will see dead branches start to show up starting at the upper crown. You may also see splits in the bark, as well as D-shaped holes where the larvae exit the tree. The larvae are flat and cream-colored and have pinchers. An adult beetle is flat and metallic green.
The anthracnose is a fungal disease that generally attacks trees in the spring and stops once the weather becomes hot. If your tree has this fungus, you will see small brown spores on the on the underside of the leaves. You also may see these sores on the small branches. Fortunately, this fungus rarely kills a tree.
If your white ash tree has the ash yellows disease, it will start to lose its vigor and will get worse over time. Leaves will turn yellow, looking much like the leaves do in the fall. The tree may lose leaves and have cankers on the branches and trunk. A distinct symptom you will see if your tree has this disease is the witch's broom. The trunk may split in different areas. This will eventually kill your white ash tree, and there is no known cure.
Caring for Your Ash Tree
Taking proper care of your white ash tree can help prevent some diseases. One thing you should do is to have your tree regularly pruned by a tree-service company so it does not become too large. This also allows the tree service to get a good look at the top branches and leaves to look for signs of disease.
Give the tree a slow-release granular fertilizer made for trees in the fall. Sprinkle the fertilizer over the ground around the base of the tree, but do not let it get near the trunk, as this could encourage infections.
Put mulch around the tree in the summer to help maintain moisture. You can use pine needles, sawdust, or chopped-up leaves.
If your white ash has a deadly disease, a tree-service company such as BCB Tree & Shrub Services will remove it from your yard to prevent the problem from spreading to other trees.