Dogwood Anthracnose: Atlanta Diagnosis & Treatment Guide

What Is Dogwood Anthracnose?

Dogwood anthracnose is a serious fungal disease of dogwood trees caused by Discula destructiva, a non-native pathogen introduced to the United States from Asia in the 1970s. It attacks leaves first, then moves into twigs, branches, and the trunk, where cankers can girdle and kill the tree.

How to Recognize It

• Tan leaf spots with purple or reddish-brown borders, often appearing first on lower branches.
• Larger brown blotches on leaves, sometimes killing the entire leaf, with dead leaves sometimes hanging on the tree.
• Spots on the showy white flower bracts during cool, wet springs.
• Sunken brown cankers on twigs, branches, and the trunk that can girdle and kill limbs.
• Unusual clusters of weak, leafy shoots (water sprouts) emerging on the lower trunk and main limbs.
• Dieback that starts in the lower canopy and progresses upward over time.

Leaf and bract symptoms typically appear in cool, wet spring weather, often within a few weeks after the tree flowers, while twig and branch dieback becomes most visible through summer and fall. The fungus overwinters in cankers and in infected leaves that stay attached to the tree, ready to spread again the following spring.

Why It Matters for Atlanta Trees

Dogwood anthracnose is considered the most serious disease of flowering dogwoods in the eastern United States and has caused widespread mortality in both forest and landscape settings. Without intervention, a heavily infected tree can decline and die within two to three years, and dead or weakened branches over walkways, driveways, or play areas can become a fall hazard. In Atlanta yards, flowering dogwood (Cornus florida) is the native species most at risk, while kousa dogwood (Cornus kousa), Cornelian cherry (Cornus mas), and Cornus florida x kousa hybrids tend to be more tolerant.

General Prevention

• Plant dogwoods in sites with morning sun and good air movement rather than deep shade, since the fungus thrives in cool, moist, shaded conditions.
• Water deeply during summer droughts, but avoid wetting the leaves and avoid high-nitrogen fertilizers, which push out the tender growth the fungus prefers.
• Rake and remove fallen dogwood leaves in autumn so overwintering spores are not sitting under the tree.
• Prune out dead or dying twigs and the weak water sprouts on the trunk during dry summer weather to improve air flow through the canopy.

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 without sanitizing tools between cuts. Unsanitized blades can spread the fungus from infected wood into healthy parts of the same tree or to neighboring dogwoods.

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 second opinions.
• Plant Health Care (PHC) for ongoing tree health management.
• TRAQ Tree Risk Assessment when the tree may be a safety hazard.

Sources

This page summarizes general information from: NC State Extension, Clemson Cooperative Extension Home and Garden Information Center, and UNH Cooperative Extension.