"The tree just died over night...."
This is the comment we typically get after insects bore into the trunk of a mature tree or even a newly planted tree. Ambrosia Beetle is one of the common boring insects in our area and it brings with it severe vascular damage and a fungus that can wipe out a mature oak tree in a matter of weeks. This insect was introduced in North Carolina around 1974 in some peach trees brought from China. They have been a problem in the Carolinas ever since. You might think that an insect that can do this much damage must be fairly impressive in size, however the chance of seeing one is extremely small. So small, in fact, that it is only about 1/10 of an inch long or around half the size of a grain of rice.
So what happened for such a small insect to invade your tree? Chances are that the tree's moisture content was low so the insects detected a chemical imbalance and moved in. This can occur from root damage, limited root space, poor soil conditions, trunk damage, lack of moisture and other stressful factors put on a tree. Unfortunately this describes many of the trees in the urban landscape.
Treating for this insect can become very difficult once it moves into a tree. Even if you can kill the insect, the fungus can be equally as damaging. Your best defense against this (and most other insect and disease issues) is a healthy tree. This can be achieved through mulching, watering, soil decompaction, and adding nutrients and organic material to the soil. If your tree is already in a stressed condition then monthly trunk sprays might be needed through the growing season.
Boring insects are usually discovered by saw dust on the lower 10 feet of the trunk and around the base of the tree. Sometimes the sawdust looks like a tooth pick. The holes they make are pin size and can be very difficult to see, especially on rough barked trees.
So is there anyone who appreciates this insect?? Well, if you are a wood worker or love a beautiful maple bowl with the fungal streaking that comes from this insect then you might appreciate a piece that looks like this:
If you suspect your trees have Ambrosia Beetles, please call your Arborist so we can help save your tree!
