Reading a few articles online isn’t going to make you an arborist. But, if you insist on making your own diagnosis here is a good check list of things to look for. My preferred use of this info would be used as your tool for interviewing professionals. Here is a form you can print up. Here we go:
- The Canopy
- leaf sizee – This one is a little tricky because leaf size will vary with site conditions. Compare your tree to like species nearby. Dwarfed leaf size is one of the first signs of stress a tree will show.
- leaf color – Yellowing leaves is a disorder we call chlorosis. It is often, incorrectly, associated with nutrient deficient soils. The reality is that chlorotic leaves are nutrient deficient, but not necessarily because the soil is deficient. Usually, there is a problem getting the nutrients from the soil to the leaves. Chlorosis is further complicated by the factor of time. When new leaves come out they are usually yellow and turn green as they develop. The longer they take to turn green, the more problematic they are. As a general rule, if your trees aren’t fully green by end of May there is definitely a major problem.
- foliage density – The number of leaves in a tree are a good indication of its overall vigor. The trick I like to tell people is to focus on the sky behind the tree. The more blue you see, the less foliage density you have. Like leaf size, this will vary with site conditions. Compare your tree with others near by to get a better feel.
- dead limb location – Trees develop dead limbs naturally. The trick to knowing if your dead limbs are an indication of a sick tree is to look at the location of the dead limbs. It is natural for dead limbs to appear in the under side of the canopy where there is lots of shade. There is nothing to worry about these dead limbs, just prune them away. If the dead limb reaches to the extremities of the canopy then you have a problem. Limbs receiving full, direct sunlight shouldn’t die.
- broken limbs – Unattended broken limbs can lead to problems. Jagged wounds don’t heal well and lead to more extensive stem decay which leads to more broken limbs.
- The Trunk
- root flares visible? – Root flares are the area where the tree’s anatomy changes from trunk to roots. If your tree looks like a telephone pole going into the ground you have a problem. It is absolutely imperative that the root flares be above ground. If you bury the tree trunk it will eventually begin to rot.
- trunk injuries – Trunk injuries are the worst kind of injuries to trees; they don’t have good mechanisms to heal these types of wounds.
- The Rooting Area
- irrigation? – Supplemental irrigation is the best thing you can do to improve tree health.(period) There is a right and wrong way to water, but that is in another article.
- drainage – Water is good, but if it doesn’t drain away your tree will die. Three days is a good benchmark to use for judging whether you have a drainage issue. Standing water on the fourth day is cause for concern. Three weeks of standing water will kill most trees automatically.
- herbicide evidencee – All weed-n-feed products for your lawn are tree killers. There are very few herbicides that kill weeds and are somewhat safe for trees. The safest ones are used as a preventative. If you are trying to kill weeds after they are there, you should spot treat with round up or pull them manually. When I am looking at a site for the first time I always look for weeds in the yard. No weeds often means herbicide usage.
- construction activity evidence – The worst part of construction damage is the months of continuous foot traffic by workers. This compacts the soil thus squeezing out precious pores that would have held air and water. The other things to look for are utility lines or anything else that would have required a trench to install. Trenches cut tree roots, and that is not good.
- root zone conditions – Two factors to consider here: a) size of rooting area, and b) likelihood of foot traffic. For a) I’d say a general rule of thumb is to have at least half the distance to the ends of the branches be impervious. For b) the size of rooting area is also a factor. If you have limited rooting area and high foot traffic that is not good.
The point of this article is to help point out many common tree symptoms. Solutions to these tree problems will vary from site to site.