What is The Background Level of Fire Blight Bacteria?
With a few rare exceptions, you cannot have classic fire blight of apple or pear blossoms without a nearby source of E. amylovora bacteria. A single active carry-over canker seems to produce enough bacteria to severely contaminate the blossoms on at least 1/4 – 1/2 acre (.1-.2 Ha). The closer to the canker, the more likely the blossoms will be contaminated, and the more likely strikes will appear, even following poor infection conditions. The more strikes in the close area, the worse the outbreak will likely be following normal, or dangerous infection conditions. With the ever-increasing incidence of fire blight in all parts of the Pacific Northwest, your source of blight may be your own orchard. If you look closely this winter while pruning, you may see blossom clusters and small twigs with dead fruit and leaves tightly attached, with a small dead area at the base of the dead shoot and blossom structure. It is possible you will be looking at Pseudomonas blossom blast, but it is more l
With a few rare exceptions, you cannot have classic, serious fire blight of numerous apple or pear blossoms without a nearby source of E. amylovora bacteria. A single active carry-over canker seems to produce enough bacteria to severely contaminate the blossoms on at least 1/4 – 1/2 acre (.1-.2 Ha). The closer to the canker, the more likely the blossoms will be contaminated, and the more likely strikes will appear, even following poor infection conditions. The more strikes in the close area, the worse the outbreak will likely be following normal, or dangerous infection conditions. With the ever-increasing incidence of fire blight in all parts of the Pacific Northwest, your source of blight may be your own orchard. If you look closely this winter while pruning, you may see blossom clusters and small twigs with dead fruit and leaves tightly attached, with a small dead area at the base of the dead shoot and blossom structure. It is possible you will be looking at Pseudomonas blossom blast
