Tree damage isn't always immediately evident. Sometimes, a tree may start to languish for no apparent reason. This could be due to a problem with the roots or could be due to a problem that's hiding beneath the tree's bark. Here are some of the things that can damage your tree below the surface of the bark.
1. Bumps and Bruises
In some cases, your tree could suffer physical trauma that damages its trunk, yet isn't visible from the outside. One common cause of trauma to tree trunks is lawn equipment. This is especially common if your tree is right in the middle of a lawn or flowerbed without a generous circle of mulch.
In some cases, a lawnmower or string trimmer could take the bark right off. But other times, it could simply bruise the tree beneath the bark so you don't even know the damage is there until the tree fails to thrive, or even starts dying.
Another way that a tree could sustain physical trauma beneath its bark is a girdling root (one that encircles the entire trunk), which you may not notice if it's below the mulch or soil. This root could strangle the tree, squeezing its interior, until it's unable to get enough nutrients and moisture to thrive.
While fungi can sometimes enter through wounds (such as pruning cuts), they can also enter a tree through the roots. Some types of fungus, such as Verticillium dahliae, may enter through a tree's roots and cause damage inside its trunk and stems. In the case of Verticillium fungi, the tree's tissues that conduct fluids and nutrients then become clogged up.
While some insect damage is obvious, other types of insects may do their dirty work entirely on the inside of the tree's trunk, without even leaving obvious entrance points. In some cases, you may need a professional to examine the tree for entry points and symptoms and determine if an insect caused the damage.
4. Wind and Storm Damage
In some cases, stress from wind or snow loading can actually cause a branch or trunk to become weakened internally. If the damage isn't severe enough to cause an actual break, you may not notice it at first. If the tree is only slightly structurally weakened, a tree service expert may be able to save it by using tree cabling or bracing.
These are just some of the ways your tree can become damaged beneath the surface of the bark. As you can see, these types of tree damage may not give immediate evidence of what the problem is. A tree service professional can help you diagnose a sick or damaged tree and provide the appropriate treatments.