Maple tree: sudden death?

Asked September 29, 2015, 4:01 PM EDT

We have a very large old maple, probably 70 feet high. We noticed the leaves starting to brown and shrivel up back in May or June. By now less than a third of the remaining leaves have any green left in them, but they are clearly going bad as well. Is this a terminal disease? Soil fungus? Will the wood go bad if we do not harvest the tree immediately--assuming that is a good option? Your thoughts? (P.S.--What may appear to be small "spots" on the leaf close-up is more likely crumbs of dried moss.)

Clackamas County Oregon

1 Response

Diagnosis of exact causes of your maple decline would require more time and investigation. The summer heat and drought has been causing quite a bit of premature leaf dieback. Given that there are still signs of life in your tree, waiting till next spring to see what life returns is a reasonable plan.

You can start the investigation into causes now however. Examine the trunk and branches, especially the forks and crotches looking for signs of discoloration on the bark, oozing sap, dead patches of bark. Various fungal and bacterial afflications sometimes kill maple parts, not necessarily the whole tree.

There are also root diseases that cause more serious whole tree decline. sometimes there are signs of this on the trunk and bark at the base of the tree.

Drought and heat alone can cause premature leaf loss and it could be mostly green next spring.