Disease update

It has been mostly wet since Saturday afternoon, Apr 21, with soaking rainfall totaling 0.9 in. Wetting Saturday likely resulted in quince rust infection of unprotected susceptible blossoms and cedar-rust infection of foliage and some fruit; fruitlets which have reached thinning size should be relatively resistant to quince and cedar rust rust infection. Wind direction during the early wetting was mostly from the west and northwest, a warning regarding the cedar tree inoculum source for rust-prone orchards. The current 24+-hr wetting period favors secondary scab.

Secondary powdery mildew lesions were common by Apr 20, evidence of our most active early season disease this year.

The fire blight outlook remains similar to that posted below, but with risk Apr 23-29 now showing as only light or moderate. However there is still susceptible bloom on many cultivars, especially in lower areas where there was frost damage, and there will probably still be some late bloom when temperatures are again warm enough to expect some risk from fire blight (Stay tuned!).