Beware of Roots and Collar Rots

By: Dominick Bierdek, Certified Arborist WI-0635A

Summer 2007 Newsletter in Adobe PDF format Root and collar rots not only affect health, but they can also affect the stability of a tree.

It is important that tree owners are aware of root and collar rots that affect trees. These problems should be of great concern because they can affect the health and stability of a tree. Any tree an owner suspects is undergoing change caused by decay should be inspected regularly.

Root and collar rots are different types of decay fungi that have negative to dangerous effects on trees. Aboveground symptoms that trees exhibit are often misdiagnosed as disease or insect damage. However, many tree ailments we see aboveground are often problems that originate from below the ground or in the base of the tree.

Root rots can infect and decay roots. While some rots kill the living root tissue, others break down the woody structure of the tree. In either case, the tree is at risk of dying, or at worst, failure. Many times decay is happening on the inside of the tree and is only noticed when fruiting bodies are produced. Most of us call these mushrooms or conks.

If you see mushrooms or conks, swells of the trunk or an extra large root flare, there may be reason to suspect decay. Certainly, many trees with decay need not be removed, but should be inspected regularly and monitored for changes. Our experienced Certified Arborists know what to look for in trees with suspected decay. It may still take further inspection with special equipment to see inside the tree to verify the level of decay and determine the tree’s risk of failure.

The best defense is to keep trees as healthy as possible. Healthy trees are less likely to be attacked by decay. It is very important to avoid damaging the base of the tree and roots with mowers, weed whips, shovels or other tools. Many decays are opportunistic and quickly take advantage of any wound opening. Also, keep mulch and soil pulled away from the tree trunk and root flare. This holds moisture against the tree and makes a positive environment for decay.

There are also some rots that are known to be very aggressive in either killing the tree or quickly making it unsafe. If one of these is found, a Certified Arborist may recommend removal as soon as possible to mitigate the tree falling and causing serious damage to people and property.

Prevention and good health are key to avoid decay. The Certified Arborists at Wachtel are your partners for healthy trees. We can assist you in keeping your trees healthy, perform tree inspections and help you make informed choices if trees need testing, removal or treatment.

© Copyright 2007 – Wachtel Tree Science & Service, Inc.

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