Help my Liberty Elms, please!
I have several lovely ‘adolescent’ elm trees (not Chinese elms!) planted along my driveway (they are between 7 and 8 years old), and nearly all of them along one side have this nasty cracking, bark lifting and peeling, and most have black tar-like patches. The leaves and tops look fine, though. There had been earlier deer damage, but that happened to the trees on both sides of the driveway, unlike the current issue. Can they be saved? I took pictures of a few of them. Thank you SO much!
Buffalo County Nebraska
First, sorry for delay in responding. It is difficult to say just what caused this trunk issue on these trees. The cause could range from deer damage to lawn moweritis, tree trimmer damage, suncald (sun beating on bark during winter which causes cells to become active and then cells are damaged by freezing temperatures to fungal canker diseases that infect through wounds, such as deer damage or sunscald.
For these trees, there is not much to do but hope for the best. Do not apply any kind of tree wound dressing to the wounds or any kind of trunk wrap during the summer. If the wound is superficial and the trees are otherwise healthy, they may close the wounds with callus growth and possibly be fine. This can be encouraged by placing a 4 to 6 foot diameter ring of wood chip mulch 3 to 4" deep around the trunk (be sure not to pile the mulch against the trunk) and maintain a moist (not saturated) soil. Avoid nitrogen fertilizer as this will compound tree issues.
For future trees, to help prevent a similar issue, use mulch around the base to avoid grass competition and "homes" for wildlife like voles or rabbits. Tough to keep deer away. Wrap the trunk of young trees, but ONLY during winter - about December 1 to mid-March to reduce the risk of sunscald.