FIRE BLIGHT: Above is a graphic from the Maryblyt 7 program. Most apple cultivars at our AREC remain near full bloom, but with later blossoms continuing to open. Later cultivars such as Rome Beauty are not yet at full bloom. The temperature and rainfall data are current through this morning, May 2. Predicted weather conditions are shown for May 2-11. The components of fire blight risk are indicated in the columns labeled B (blossoms open), H (degree hours for epiphytic bacterial populations), W (wetting by rain or dew), and T (average daily temperature 60 F or above). Based on predicted temperatures and wetting, the risk column shows that fire blight risk will be high, lacking only wetting for infection, for May 4. Risk then remains moderate to high or at an infective level through May 11.
CAUTION: Be aware that risks can change quickly with unpredicted warmer temperatures and wetting. In high-risk situations, a protective streptomycin application is recommended ahead of predicted infection conditions, or with applications that cause wetting when all other infection conditions have been met.This graphic will be updated May 5. The weather conditions used in the predictive part of this graphic come from the Weather Channel for Winchester, supplemented by site-specific data from SkyBit Inc.
