Wetting periods favorable for scab and cedar-apple rust infection occurred May 5-6 (13 hours wet at 63°,< 0.01 in. rain) and May 8-9 (split wetting, 18 hours at 64°, 0.4 in. rain). There are still plenty of active rust galls giving off inoculum for foliar infection. Fruit are no longer susceptible to rust infection.
Through May 10 there have been 30 days favorable for powdery mildew infection since spores were first available Mar 19.
There was scattered hail in some areas of Frederick County May 2 and fire blight shoot symptoms related to trauma blight infection are predicted to appear May 15.
The above wetting periods were also favorable for scab infection on peaches and nectarines.
Disease management information directed mostly to the Frederick County Virginia tree fruit industry, updated as needed throughout the growing season. Keith Yoder, Virginia Tech Agricultural Research and Extension Center, Winchester, Virginia
About Me
- Keith Yoder
- Professor Emeritus of Plant Pathology, Virginia Tech Ag. Research and Extension Center, Winchester, VA
