This may seem like a simple question, but it is not. Here’s the “X” factor that makes it hard to know if your tree is sick: trees have energy reserves. This means that when something afflicts your tree, the tree is going to fight a good battle without you ever knowing it. But, there are some subtle signs to look for. Here are the secrets you need to know.
Let’s start with the leaves; that’s the only thing most people take notice of anyway. The first thing to look for is color. Ninety nine percent of tree species are supposed to have a very dark, rich-green colored leaf. If the leaves aren’t green, they’re usually some shade of yellow-green or brown. Obviously brown is bad, this is serious. However, yellow is serious, too (often the precursor to brown). The “yellowing leaves” condition is generally refered to as chlorosis (klor-osis), which can be caused by many things. The next leaf characteristic to look for is leaf size. One of the first symptoms of many tree disorders / stresses is for the tree to shrink leaf size. This symptom can be trick for non-arborists. Healthy leave size varies from species to species and even from location to location. For example, a live oak located near lake Austin should have leaves about 2” long, whereas, live oaks in the rocky slopes of the hill country should have leaves about 1 ¼” long. The last leaf characteristic to look for is leaf shape. Again, this one can be tricky for non-arborist because you’ll need to know what the leaves are supposed to look like.
The other place to look, besides the leaves, is at the ground. Very often trees main problems are that we have damaged their roots or rooting environment. Cutting roots, compacting soil and filling soil around tree trunks are the most common injuries. Most of the time these activites are related to some sort of construction activity. I doesn’t take much; 75% of tree roots are in the top 12 inches of soil, and they do extend all the way to the surface.
Determining if your tree is sick or stressed is just phase one. You’ll then need to make a proper diagnosis so that a comprehensive treatment program can be implemented. It’s always a good idead to hire an arborist if you really have a sick tree. Reading about something isn’t replacement for field experience. If you can’t afford to hire a tree guy for their service to provide treatments, caughing up $150 for a consulting fee will save you great amounts of time, money and frustration in the long run.