Today, lets talk about tree wound spray, or the material some use on the ends of a cut limb.
Believe me, they are only cosmetic and serve no valuable service to tree. As a matter of fact, the use of tree wound material that you can either spray or paint on a trees wound actually increases the tree's chances of being injured by insects, disease or both for that matter.
Thirty years ago, tree wound compounds were recommended. However, since then, science has proven it hurts a tree rather than helping a wound to heal. Keep in mind that few trees are able to reach maturity without receiving one or more wounds either from environmental conditions or man made pruning.
Trees don't heal in the true sense of the word. Injured tree tissue is never repaired and returned to the former state as in a cut on your hand. Trees react to injury by closing the wound and compartmentalizing or isolating the injured tissue from the surrounding tissue. Use of tree wound materials does not alter the sequence of events leading to decay.
Here are some hints when a tree is injured and a wound exists. First of all, clean the tree wound by trimming away the loose injured bark. Try to shape the wound into an oval, but don't cut out too much to get this shape. Be sure to remove dead or dying or even weak branches from the wounded tree.
Cuts should be made up against the trunk, but just outside the branch collar or the swollen area where the branch connects to the larger branch or trunk. Be sure to fertilize and water the injured tree to increase plant vigor and the rate of closure of wounds. The best time to fertilize trees that lose their leaves in the fall is spring and then again in the fall. For evergreen trees, fertilize in the spring and early summer only.