Diseased tree - Ask Extension
Can you please tell me what’s wrong with our grafted weeping cherry tree?
Knowledgebase
Diseased tree #946588
Asked October 06, 2026, 11:36 AM EDT
Can you please tell me what’s wrong with our grafted weeping cherry tree?
Macomb County Michigan
Expert Response
We are seeing signs of possible sap or dark oozing coming out of the tree, there’s white fuzzy substance on the trunk in spots. I thought maybe the pictures would help. Is there an arborist at MSU extension that would come to my home to assess?
Hello
This is gummosis a common reaction to stress or injury on cherry trees.
https://yardandgarden.extension.iastate.edu/encyclopedia/gummosis
As the article states, give the tree good overall care: water during droughts, clear extra soil and mulch away from the base of the trunk, avoid wounding the bark, correctly prune branches, and remove diseased wood where possible.
Here are some guides on correct pruning technique(see page 9) https://extension.purdue.edu/extmedia/FNR/FNR-506-W.pdf
Check that the base of the trunk is not too deeply buried in soil or mulch. The base of the tree flares out to the beginning of the main roots and this area should be at soil level. This area is called the root collar or the root flareand is an important source of oxygen exchange for the root system. Here is a bulletin showing a properly mulched tree(see printed pages numbered 2 and 11).
Minimizing stresses on the tree is the best way to extend the life of the tree.
This is gummosis a common reaction to stress or injury on cherry trees.
https://yardandgarden.extension.iastate.edu/encyclopedia/gummosis
As the article states, give the tree good overall care: water during droughts, clear extra soil and mulch away from the base of the trunk, avoid wounding the bark, correctly prune branches, and remove diseased wood where possible.
Here are some guides on correct pruning technique(see page 9) https://extension.purdue.edu/extmedia/FNR/FNR-506-W.pdf
Check that the base of the trunk is not too deeply buried in soil or mulch. The base of the tree flares out to the beginning of the main roots and this area should be at soil level. This area is called the root collar or the root flareand is an important source of oxygen exchange for the root system. Here is a bulletin showing a properly mulched tree(see printed pages numbered 2 and 11).
Minimizing stresses on the tree is the best way to extend the life of the tree.
