AMHERST, NH

Even though trees can't talk, they exhibit many signs that can indicate how they feel. According to the National Arborist Association, early fall is a good time to "read your trees." Here are some tree characteristics landscape maintenance contractors may want to look for:

Color of the Leaves

•Off-color leaves may be an indication of a nutrient deficiency in the soil, or they may be a sign that, for some reason, the tree's root system is incapable of extracting the necessary nutrients. The pattern of discoloration can be important. For instance, iron chlorosis causes progressive yellowing of newly emerging leaves in oaks and other species. Nitrogen deficiency also causes yellowing, but affects the oldest leaves the most.

•Certain trees are susceptible to diseases that cause a distinctive change of leaf color.

•Premature fall coloration during the summer is generally an indication of a problem below ground that is creating stress conditions for the tree.

Misshapen Leaves

•An upward curling of the leaf margin-- kind of a cupping effect-- is the classic symptom of damage from herbicides.

•Distorted leaves may be evidence of sucking insect damage, or the presence of a disease organism. Distorted leaves with brown, necrotic (dead) tissue could mean the tree has anthracnose, a problem in many areas across the country this year.

Thinness of the Canopy

•Typically, when the uppermost part of the tree's canopy begins to thin, the condition is characterized as decline. However decline can have several causes, sometimes acting in combination, that are treatable. Does your tree look like a telephone pole-- that is straight-- where it enters the ground, or does it have a natural root flair? The combination of thin crown and telephone pole appearance usually indicate that the tree's roots have been covered with fill.

•The combination of thin crown and flat trunk on one side are the symptoms of a root that is literally strangling the tree.

•Thinness of branches on the inside of the tree canopy may simply mean that interior branches are being shaded. Proper pruning may benefit the tree.

Landscape professionals may contact professional arborists at the NAA at 800-733-2622, or log onto www.natlarb.com.