What Are the Spots on My Crab
Apple Tree?

Chris, along with UT/TSU extension agent Joellen Dimond shed some light on the appearance of unsightly brown spots on the leaves of a Bartlett resident's crabapple tree. A big culprit for these kind of spots is cedar-apple rust which is caused by a spores that grow on cedar trees and are transferred to the crabapple tree via the wind, rain or leaf contamination. The cedar-apple rust fungus spends part of its life cycle on the ceder tree and part on an apple tree. While this condition does not go away by itself it isn't deadly to the tree. You can minimize the appearance of cedar-apple rust by practicing good sanitation and by using fungicide.

Related Resources:
Cedar-Apple Rust
Cedar-Apple Rust
Crabapple