Wood Decay in Trees: Is Your Tree at Risk of Failure?
Wood decay is caused by fungi, and when it is present in trees, it weakens the wood and makes the tree more susceptible to failure. To maintain your trees’ health, it’s a good idea to be aware of the different types and indicators of decay. Getting your tree assessed and treated regularly can help you prevent advanced decay.
Types of wood decay
There are three types of wood decay: white rot, brown rot, and soft rot. Each affects the tree differently but ultimately causes it to be weak and have a higher risk of failure. While fungi are not restricted to a specific location in the tree, identifying the area of the tree that is being affected by rot is useful in assessing the risk and what a professional arborist may be able to do to mitigate that risk. There are various identifications based on the location of the fungi.
Branch rot is caused by fungi located in the branches of the tree
Heartwood rot is decay in the center, or heartwood, of the tree
Sapwood rot is decay located in the sapwood, in which bark and cambium may be damaged
Basal rot is caused by fungi located in the base or lower trunk of the tree
Root rot is decay in the roots
Possible indicators of decay
One of the reasons that decay so commonly causes tree failure is that it’s not always easy to detect, especially if you are not a professional and don’t regularly take a close look at your trees. However, there are a few things to look for that may be indicators of decay.
Fruiting bodies, conks, and mushrooms
The fungi that cause decay can create fruiting bodies such as conks and mushrooms. Your tree can have wood rot without also having conks and mushrooms, but if you do see them, your wood may be rotting. In particular, these fruiting bodies usually are an indicator of sapwood rot. If you notice these on your trees, it’s a good idea to have an expert evaluate your tree for rot.
Tree cuts and wounds
Cuts and wounds from previous bad pruning cuts, particularly from tree topping can indicate decay. This is because when large cuts are made, such as those from being topped, the tree may not be able to heal or close its wound due to its severity. Decay then has free access to move down the tree. This is one of the many reasons that you should not have your trees topped. If you do not see a visible wound or cut on your tree, another way to detect it is by looking for loosened or broken bark. This can be a tell that the tree has been injured and thus is vulnerable to decay.
Birds nesting in tree cavities
Being aware of birds in your trees helps you detect tree rot, as they will dig out decayed wood to create a place to nest, or they will nest in a large cavity already in the tree which is likely caused by decay. Similarly, honey bees may also make their hives in cavities in a tree. Small cavities do not necessarily mean that the tree has wood rot, but it’s a good idea to have your tree looked at, especially when the cavities are large.
Insects or pests
Pests such as bark beetles tend to attack trees that are under stress. The presence of bark beetles could be an indicator that your tree is experiencing decay, which drew in the bark beetles.
How can you prevent tree decay?
Tree decay can lead to tree failure and the damages that come from that. Learning about how you can prevent this from happening can save you from the hassle of expensive damage to your trees and property down the line.
Have your trees pruned regularly
Having your trees regularly pruned can help in preventing that from happening. Many severe wounds that lead to tree rot are a result of poor pruning. This is why it’s not only important to have your trees pruned, but they must be pruned correctly following proper pruning practices or by certified arborists.
Deadwood removal
Dead branches tend to decay quickly which is why having them removed is critical. Additionally, when a dead branch breaks off, it can expose your tree's heartwood, creating a path for insects, pests, and fungi to settle in your tree. Thus, pruning for deadwood removal is a recommended way to prevent your tree from decaying.
Use caution with machines and equipment around trees
Lawn care equipment such as mowers and string trimmers can create wounds on trees if they are not used with care. When operating, keep them at a distance from your trees to avoid wounds, which can lead to decay. Heavy equipment such as those used during construction can also create wounds to your trees. You can mitigate this risk by understanding how to prevent tree damage during construction.
Ensure good growing conditions
Wood production is a key factor in a tree being stable and healthy. To manage your tree's health and prevent decay, making sure your tree's growing conditions are optimal is important. Properly watering your trees can make a big difference because it helps give them the nutrients it needs to heal pruning cuts and defend themselves from infections caused by rot.
In order for a tree to maintain its overall health, having it regularly inspected is critical. If decay is detected early on, the chances of you being able to control it and stop it from spreading to other areas of the tree are much higher. If you want your tree's health evaluated, or to learn if it is at risk of failure, schedule a no-cost consultation online or with one of our field representatives to have one of our local, professional arborists consult with you.