Stressed tree

Asked June 24, 2016, 8:23 AM EDT

I planted a crab apple this spring and within two weeks most of the leaves started to wither and die. The tree appears relatively healthy as a second set of leaves is pushing out. Question: Is there anything I can do now to help the tree along? In particular, can I (should I) fertilize and if so how often and with what type of product. Thanks, Jeff W.

Hamilton County Ohio

1 Response

Hi Jeff,

This could be an apple scab disease - it’s a very common problem for crab apples. The main symptoms of the disease are leaf and fruit spots. Very susceptible trees become defoliated by mid-summer, which weakens the trees over time.

First thing is to rake up and destroy fallen leaves - do this in the fall also. Prune the tree so the branches are spaced well enough apart from each other so that air can move through the trees and dry the leaves quickly. Also, remove vigorous upright suckers and water sprouts that have formed along the main trunk. Your tree is trying to produce more leaves, using the energy reserves it needs to get through the winter. As the tree becomes more stressed, it can be susceptible to insects and other diseases. The apple scab won’t kill the tree, but the chronic weakening will. Fungicides won’t help at this time as they are preventative - but consider for early next spring when the first green leaf tips emerge. Also, fertilizing at this time won’t help. For the future - Secrest Arboretum in Wooster, Ohio found that of the 287 crabapple varieties, only 5 showed disease resistance: Beverly, Sargentii, Jackii, White Angel and Silver Moon.