Hi Folks, This is my first post so bear with me. We have a couple of large willows that have developed what I can only describe as a boil or a canker? I have attached a couple of photos. Can anyone help me determine if these are fatal or dangerous to my trees?
Yes, a canker. Not usually fatal, but it is potentially dangerous in the longer term, as the diseased area expands it leaves the trunk weak and liable to break in a storm. So if the tree is anywhere that it could hit anyone in falling, it might be best to remove it.
Thanks, Michael F, for the info. Is there anything I can do to rid the tree of this ugly growth? Fortunately, both trees are down near the pond so they won't threaten any buildings if a limb fails.
There are several disease organisms that could cause the symptoms; I suspect that accurate identification, and any possible treatment, might need an on-site inspection by an ISA-certified arborist. Even then, it may well be untreatable as the disease has covered such a large part of the stem's circumference. Basically - willows are fast-growing, short-lived trees. One can't expect them to stay in perfect health for a long time! When the trunk does break at the canker, you'll get a massive re-growth of new sprout stems from the trunk below the break, which will soon rebuild a new crown (though all the new branches will in turn be liable to break from time to time!). If you are able to leave it without risk to anyone, it is good to do so, as old breaking-up willows like this are very good for wildlife, plenty of nest holes for birds, etc., and full of insect food for woodpeckers.
