Foliar blight on madrone was very noticeable in 2011 and may be due to periods of extreme cold. The fungus Phacidiopycnis washingtonensis has been isolated from madrone foliage with blight symptoms . This fungus also causes storage rot in apples. We have isolated it from madrone foliage in western WA.
We would like to create a map of the foliar blight in the western US. If you are out in the woods and have noticed this problem on madrone, you can help. We are also interested in the health of madrones in areas without severe foliar blight symptoms. Digital photos of the trees and the site are also welcomed.
The blight affected the current years (2010) foliage, which will be shed at the end of summer. New foliage is emerging now (2011) and is usually asymptomatic.
Send in your own description. These will help us map where the madrones are most and least severely affected by the blight. Note whether budbreak is occurring or if the trees are in flower.
If you can include a sample of infected foliage, collect leaves that look like those in the photograph and wrap them in damp paper towels in a plastic baggie. Best results will be obtained from leaves that still have some green on them and are not dried out. For each tree sampled, also include some information on this brief survey form.
|From the Office of the Washington State Climatologist|
More photos and descriptions of symptoms:
|Foliar blight symptoms|
|Fall webworm symptoms|
|Branch canker and dieback symptoms|