"Money does grow on trees" as most Palos Park Homeowners know. Most of us moved to Palos Park because of the woodsy look, and we know that this is the look that will bring others to our community. Recent research says that healthy trees can add up to fifteen percent to property values, and that an attractive well maintained landscape beautifies the whole neighborhood.
But, every year there are some trees that just don't look healthy. They show a loss of vigor, pale green or yellow leaves, early leaf drop, early fall color, and dieback of twigs and branches. These trees are showing signs of stress which may lead to tree decline.
Stress on trees can be caused by environmental conditions such as poor weather -extended periods of drought or wetness, or extremely hot or cold weather. Stress also is caused by soil compaction, or changes in drainage due to change in grade by filling over or cutting away the root zone soil. Other stressors are mechanical damage, excessive use of or improper pesticides, nutrient imbalances, and excess salt accumulation in winter. These stressors weaken the tree, contribute to tree decline, and can lead to the death of the tree.
It is difficult to reverse tree decline once it starts, so the best strategy is prevention. When planting, select trees with their mature size in mind. Select disease resistant varieties. Check to see if your site has the kind of soil your choice requires. For example, a pin oak requires an acidic, well drained soil, while a weeping willow requires a moist soil with poor drainage.
Trees weakened by environmental conditions are subject to secondary agents such as bacteria, fungi, and viruses. In our area, the most common diseases are anthrocnose of sycamore, oaks and other shade trees, Dutch elm disease, fire blight, apple scab, cankers and oak wilt. Insects can easily move in on a tree that is in stress. Aphids, Asian long horned beetles, carpenter ants, pine moths, gypsy moths, and sawflies can cause much damage to trees.
The Tree and Shrub Handbook, published by the Morton Arboretum is available at our library and is a very good source for help. All of the above problems and many more are discussed with suggested remedies. Ask the librarian to help you find it. Also, one can get free advice by calling the Morton Arboretum Plant Clinic between 1 :00 and 3:00 p.m. on weekdays. (630-719-2424)