Hello - We have a crabapple (I believe) tree that's probably about 30 years old. Every spring it's gorgeous, but immediately after it's done flowering about 50-60% of the leaves get spotted and yellowed and fall. Throughout the summer more leaves follow. It has been getting worse over the past few years and this year is especially bad - I would bet 75% of the leaves are gone already. Is this a treatable issue or is the tree just old and dying?
Barry County Michigan
Thanks for your inquiry.
It sounds like your crabapple is susceptible to apple scab. This will not kill your tree, but causes it to have spots on the leaves and for the leaves to fall prematurely. Here is an MSU Extension article that explains more about it:
What you can do to prevent an increase in infection, is rake up the infected leaves and destroy them. Also, make sure your tree does NOT receive additional stressors, such as drought, which will weaken the tree more. Be sure your tree gets at least 1 inch of water per week, especially if there is no rainfall.
If you ever replace or plant a new tree, look for an apple scab resistant variety.