Fire Blight in Washington
HIGHDisease
Fire Blight is currently active in Washington. Watch your susceptible trees closely and act early.
About Fire Blight
A bacterial disease that primarily affects members of the rose family, including apple and pear trees. It can destroy entire orchards in a single season. Bacteria spread rapidly during warm, wet spring weather through blossoms and wounds.
Symptoms to watch for
Blackened, shriveled blossoms and shoot tips that curve into a shepherd's crook shape, bacterial ooze droplets on infected tissue, reddish-brown water-soaked bark, rapid dieback of branches
Trees at risk in Washington
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Treatment options
Pruning Infected Branches
Cut infected branches at least 12 inches below visible symptoms during dry weather. Sterilize pruning tools between cuts with 10% bleach or 70% alcohol solution.
Streptomycin or Copper Spray
Antibiotic (streptomycin) or copper-based bactericide sprayed during bloom to prevent blossom infections. Timing based on disease prediction models like MaryBlyt or Cougarblight.
Resistant Cultivar Selection
Planting fire blight resistant apple and pear cultivars. Resistance levels vary, and even resistant varieties may be infected under severe disease pressure.
Recommended Products & Tools
Helpful supplies for managing Fire Blight. Always read and follow label directions, and confirm a diagnosis before treating.
Protectant spray for many bacterial and fungal diseases.
For the rare case sealing is advised (e.g., oaks in oak-wilt season).
Sharp, clean cuts to remove affected wood — a tree-care essential.
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Need help with Fire Blight in Washington?
Connect with ISA Certified Arborists serving Washington:
Browse all Washington arborists →Frequently asked questions
Is Fire Blight in Washington?
Fire Blight is currently active in Washington. Watch your susceptible trees closely and act early.
What does Fire Blight look like?
Blackened, shriveled blossoms and shoot tips that curve into a shepherd's crook shape, bacterial ooze droplets on infected tissue, reddish-brown water-soaked bark, rapid dieback of branches
What trees does Fire Blight affect in Washington?
It affects Eastern Redbud, Apple, Pear. Susceptibility varies by species.
How do I treat Fire Blight?
Options include: Pruning Infected Branches, Streptomycin or Copper Spray, Resistant Cultivar Selection. Confirm the diagnosis before treating, and consider a certified arborist for high-value trees.