Fire Blight: Atlanta Diagnosis & Treatment Guide

What Is Fire Blight?

Fire blight is a destructive bacterial disease caused by Erwinia amylovora that attacks trees and shrubs in the rose family (Rosaceae). The bacterium enters through flowers, new shoots, and wounds in spring, then moves through the tree, killing twigs, branches, and sometimes the entire tree.

How to Recognize It

• Branch tips and young shoots suddenly wilt and turn brown to black, looking scorched as if burned by fire.
• Wilted shoots bend over at the tip in a distinctive "shepherd's crook" shape.
• Dead leaves cling to infected branches instead of dropping off.
• Blossoms, fruit spurs, and small fruit darken, shrivel, and stay attached to the limb.
• Sunken, dark, water-soaked cankers form on bark, often with a clear or amber-colored ooze seeping from cracks.
• Affected branches die back from the tip toward the trunk.

Infections typically begin in spring when temperatures reach roughly 65 degrees and warm, wet, humid weather coincides with bloom. Symptoms spread fastest through late spring and early summer, then slow in hot, dry weather, while the bacteria overwinter in cankers and become active again the following spring.

Why It Matters for Atlanta Trees

Fire blight is one of the most damaging diseases of Rosaceae trees in Georgia and can kill highly susceptible trees in a single season. Once the infection moves into the trunk or main scaffold limbs, the tree is often lost, and the dead or dying limbs that remain become a safety concern over driveways, structures, and walkways.

In Atlanta landscapes, the disease most often shows up on ornamental pears (Bradford and other Callery pears), flowering crabapple, apple, hawthorn, serviceberry, photinia (red tip), pyracantha (firethorn), flowering cherry and plum, loquat, and quince. Catching it early, while infection is still confined to small twigs, gives a tree the best chance of survival.

General Prevention

• Avoid heavy nitrogen fertilization, which pushes soft, succulent growth that is highly susceptible to infection.
• When planting new trees, choose fire blight resistant cultivars of apple, crabapple, and pear.
• Prune during dry weather in winter dormancy when the bacteria are inactive, and disinfect tools between every cut to avoid spreading the disease.
• Inspect susceptible trees in spring and have suspicious wilted shoots removed well below the visible damage as soon as they appear.

What NOT to Do

• Do not self-diagnose. Many tree problems look alike, and treating the wrong one wastes time and can harm the tree.
• Do not apply fungicides, insecticides, or other chemicals without an arborist's specific recommendation. Wrong product or wrong timing makes things worse.
• Do not prune symptomatic limbs during wet spring weather, and never make multiple cuts without sanitizing tools between each one. Unsanitized pruning is one of the fastest ways to carry the bacteria into healthy wood.

Related Services

For most diagnosis and treatment questions, the right starting point is one of our services:

• ISA-Certified Arborist Services for diagnosis, consultation, and a second opinion.
• Plant Health Care (PHC) for ongoing tree health management.
• TRAQ Tree Risk Assessment when a declining tree may be a safety hazard.

Sources

This page summarizes general information from: UGA Extension, UGA Extension (Middle Georgia Gardener), and University of Illinois Extension.