Sick crabapple tree

Asked July 11, 2020, 1:25 PM EDT

My crabapple tree has a fungus. Can somebody look at it and advise treatment? I live in Haslett. Jim Dawson 2380 Barnsbury E Lansing 49923

Ingham County Michigan

1 Response

Are there any cedar trees in the area? There are two common rusts that affect the foliage of crab apples: cedar-apple rust and cedar-hawthorn rust. Both complete part of their life cycle on cedar trees. Between the two of them, cedar-apple rust also tends to infect the fruit and foliage, so if you start to see signs of disease on the apples, that’s a good sign it is cedar-apple rust.

Spraying a fungicide is usually not recommended to protect trees because trees can often tolerate infection. The spots on the foliage may just be an eye sore. You can read more about these rust fungi and management here: https://extension.umn.edu/plant-diseases/cedar-apple-rust

We are not able to travel at this time, but you can call an certified arborist and they may be able to come out and consult with you about your tree. You can use the International Society of Arboriculture "Find an Arborist" tool: https://www.asm-isa.org/content.aspx?page_id=22&club_id=883139&module_id=274045

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