Question and Answer: What to Do About Tree Cavities

A large Pecan tree with decayed cavities from old cut wounds.

Published March 29, 2013, By NEIL SPERRY and STEVE HOUSER

Question: We have a large pecan tree that is critical to our landscape and our house. It is ten feet in circumference. Ten years ago a tree man removed two large branches. Recently, to our dismay, we noticed that there is a good bit of decay where those limbs were. Should we fill the decayed areas? Should we cover them? What can we do to stop additional rot? P. and A.K., northern Collin County

Answer: To get the best possible help here, I went to my friend Steve Houser of an expert tree care company in Dallas/Fort Worth. Steve and Bill Seaman from their company share the wonderful tree information here in each issue of e-gardens. Here are Steve's suggestions. (Thanks, Steve!)

"As a general rule, arborists do not recommend filling cavities in trees or decayed areas. There is also not an effective way to repair, correct or reduce, rot and decay in trees. You may have noticed the tree is growing new tissue on the sides of the cut wounds which will eventually grow together to seal off these wounds. As it does, this part of the trunk becomes stronger to help offset the loss of strength from the decay. It is a part of a tree's natural response to wounds. If you are concerned about the strength in this area, it could only be fully evaluated by a professional arborist fully accessing the conditions related to the entire tree as well as the site."