At our AREC we recorded wetting from 7:15 PM Mar 23 - 10:30 AM Mar 24, about 85% of the duration of wetting required for scab infection at temperatures that ranged from 49F down to 37F. But temperatures and area showers were variable earlier on March 23 and some local areas may have had their first scab infection. Wetting occurred north of Winchester by 6 PM while the temperature was at 55F; other areas had showers near noon March 23 and may have remained wet longer. Scab protectants applied before this wetting probably weathered through the rainfall which totaled about half an inch. At our AREC, apple bud stage varies from 1/2"- green for York (shown above) and Rome to tight cluster for several cultivars including Gala, Red Delicious and Idared. Where no fungicides have been applied and length of wetting is marginal or in doubt, it would be prudent to include one with after-infection control in the first application. Also, consider that powdery mildew spores are now available for infection during dry weather 53F and higher, and cedar-apple rust gall spore horns are extended to more than a half-inch, indicating potential for rust infection with the next rain in the mid-50s and higher.
