Question
i have what i thought was a healthy crab apple tree that bloomed profusely this spring then all of a sudden there are clumps of gray bark-like patches all over the trunk and branches. The leaves on those branches are dying very quickly. This disease has skipped the apple tree right next to it but has attacked a plum tree on the other side of the apple??? The same clumps are also appearing on a patio umbrella that is in the vicinity. Help!!!

In another part of the yard I am seeing round white spots on the trunk of an ornamental maple tree and on one of my huge Fir trees that is about 50 years old???
We live on Vancouver Island in British Columbia, Canada and we  had about 3 weeks of continual rain but have had sun for the last week or so. What do I do?

Answer
Samanth:
These gray bark like patches may be lichens which do not by themselves cause a disease. We see these on older trees and shrubs and on these plants that are stressed for another reason than the lichens. They are more of a result than a cause of decline. See this bulletin (below at the website)that I prepared on lichens.

http://www.uaex.edu/Other_Areas/publications/PDF/FSA-7554.pdf

The white spots/patches on your maple and fir may also be lichens.  You can see other pictures on Google Images. They come in an assortment of colors and composition.  If you cannot match up a photo, you are welcome to send me a photo as an attachment.

Regards
Steve