White stuff growing on leaves and branches of a crab apple tree - Ask Extension
I have what I think is a crab apple tree in my front yard, picture attached. It appears to have some kind of disease. There is a lot of white stuff gr...
Knowledgebase
White stuff growing on leaves and branches of a crab apple tree #871980
Asked June 06, 2024, 10:41 PM EDT
I have what I think is a crab apple tree in my front yard, picture attached. It appears to have some kind of disease. There is a lot of white stuff growing on the leaves and at the places where branches have been pruned. Wondering if you know what this is and if there is a treatment for it that works? Any direction you could point me to would be greatly appreciated. Would love to save it as it's so beautiful especially in the spring bloom. I live in Wheat Ridge Colorado.
Jefferson County Colorado
Expert Response
- Hello, and thank you for contacting us.
A few questions for you:
- when did you first notice this issue?
- I'm noticing in the photos that this seems to be occurring on the margins of three prior pruning wounds on the tree. How long ago were the limbs removed? Also, how much of the limb remains? In each case, it looks like there is very little if any edge left from the limb.
- if the limb was cut flush with the tree trunk (right up against the surface of the tree trunk) it may have damaged the vascular system of the tree, which has caused oozing.
- About the white substance: is it hard, soft, sticky, smooth, or is it slightly gritty in places? Is there any softer/newer-seeming ooze, or is it all dried/hard?
- Are there any other problems with the tree, such as discolored leaves, lack of fruit, other damage to the bark?
Thank you -
Jeffco Volunteer Diagnostician Annette
