Ornamental & Tree Diseases

The largest shade tree in my front yard appears to be dying. One side of the tree looks fine, but the side closest to my driveway has dead branches and didn't leaf-out this spring. Since this tree, a maple, shades my patio and has (at least it used to have) beautiful fall foliage, I'm concerned that I might lose it. Any ideas what could be causing the problem?

It sounds as though you have a real problem with this tree, since in most cases top dieback, even if it's confined to just one side, is an indication the tree has suffered major damage of some type. Since it's really tough to diagnose reasons for tree decline without seeing your tree, I suggest that you contact your County Extension Office for assistance.

Your County Extension Agent or Horticultural Agent will tell you the majority of landscape tree problems are not caused by fungi, bacteria, or other biotic agents of disease, but rather by abiotic factors (non-living agents of plant disease).

For example, you mentioned the problem is on the side of the tree closest to your driveway. If the driveway was constructed in the last year or so, and the root system was damaged, the problem with your tree could be related to this disturbance. Or, has a grade change been made lately? Mature trees cannot tolerate addition or removal of soil in the root zone and this can lead to problems. Is the tree faced with poor drainage or excess moisture. Even with good external drainage along a slope, poor internal drainage of the soil following extended rainfall may drown the roots and cause tree decline. Or, the decline could be related to cold injury. Large over-mature trees are generally more susceptible to extended periods of extreme cold, or rapid temperature fluctuation (i.e., changes from seasonal temperatures to extreme cold within a few days) before trees have reached full dormancy.

For further information on possible factors which could be involved contact someone from your County Extension Office. Also, refer to Soggy Soils Lead to Tree and Shrub Problems, and Trees and Weather-Related Stress.

What about your tree's chances of survival? Better wait for a diagnosis of the problem. Sometimes trees showing distress can be rescued with appropriate care, but most of the time when you observe top injury, too much damage has already been sustained by the root system for recovery.