My good friend Julie requested why the trunk on her maple tree was splitting vertically. I’ve a pin oak with a splitting trunk. Why? In response to Cornell College, bark splitting can happen at numerous occasions of yr and for quite a lot of environmental causes.

Whereas splits are extra frequent on the trunk of a tree, branches might also be affected. Bark splitting is just not normally deadly, though the open wound can permit the entry of decay-causing illness organisms.

Generally splitting is a manner for the tree to open up outer layers of useless bark, which can’t develop. The crack then permits the tree to develop in diameter. Or, typically the tree is rising so shortly it types a vertical crack.

Splitting in winter or early spring is also known as a frost crack. Late fast fall development on account of heat temperatures, excessive humidity and excessive ranges of nitrogen might make bushes extra vulnerable to frost cracking throughout winter, significantly on the south or west sides of the trunk. To discourage this, don’t fertilize bushes late within the rising season, except you fertilize after leaf drop and dormancy. Skinny-barked bushes, reminiscent of maples and fruit bushes, can expertise sunscald within the winter as a result of they haven’t any leaves to shade their trunks.

The injury might not present up till the summer season. Gentle-colored tree wraps may be utilized within the fall to cut back sunscald. They have to be eliminated after the chilly climate has handed the next spring. Additionally, in spring and summer season, dry climate that slows development adopted by moist climate or higher rising situations can encourage a big spurt of vigorous development, which might provoke development cracks. I believe Julie’s tree might have gone via a dry spell adopted by her growing the water. Now the tree desires to develop.

Sometimes, a circling root on the base of the trunk squeezes the trunk stopping moisture and vitamins from transferring up and down the tree correctly. The constriction finally ends up splitting the trunk. My oak might have a circling root.

Don’t put tree wound paints or tar over cracks. These merchandise don’t assist a tree to callus over a wound. Preserve your tree wholesome and vigorous so it might probably compartmentalize and callus over the wound by itself. To assist a tree do that, fertilize every spring and provides it sufficient water regularly, together with in fall and winter. The Cornell website I discussed above outlines a process for “tracing the bark across the cut up” to assist in wound therapeutic. Tracing bark entails utilizing a pointy, disinfected knife to chop again the ragged bark to create a clear edge to hurry callus improvement.

— JoAnne Skelly is Affiliate Professor & Extension Educator, Emerita, College of Nevada Cooperative Extension. She may be reached at skellyj@unr.edu.