We have a lovely crab apple tree on our front lawn. Two weeks ago it was healthy and covered in blooms, now all but the very top looks like it is dying and the leaves are brown with grey veins. We’ve had lots of rain so we aren’t concerned about enough water. We can’t see any bugs. How do we save it? Thanks!
Thank you for contacting Toronto Master Gardeners about your ailing crabapple tree. I have researched crab apple diseases and fire blight, caused by the bacterium Erwinia amylovora, is a distinct possibility and thrives in a rainy environment.
The Penn State document cited below, lists the possible diseases, and provides a description and photographs of each as well as cultural and management practices.
This site maybe helpful as well https://www.omafra.gov.on.ca/english/crops/facts/fireblight.htm
We wish you well in saving your tree. Avoid providing nitrogen which nurtures new succulent growth, and disinfect your tools when pruning away diseased tissue.