Sycamore: Sycamore anthracnose
categories: Ornamental trees Ornamentals Sycamore Sycamore Diseases
revision date: 2022-11-29 12:00
Photo by: R.S. Byther
Biology
Sycamore anthracnose is a fungal disease affecting buds, leaves, and shoots. Young leaves appear brown and crinkled, with small to large dead areas often occurring along the main vein or on leaf margins. Infected leaves often drop from the tree, sometimes resulting in severe and repeated defoliation. Twigs and branches can develop infections as well, causing twig dieback. Regrowth at the base of killed twigs often results in a witches’ broom symptom. The disease is favored by wet weather in the spring, which spreads infection from twigs to emerging leaves. California sycamore (Platanus racemosa) and American sycamore (P. occidentalis) are particularly susceptible.
Management Options
Use Integrated Pest Management (IPM) for successful plant problem management.
Non-chemical Management
Select non-chemical management options as your first choice!
- Provide proper culture. Healthy trees are more tolerant of leaf loss and recover more quickly.
- Rake and destroy fallen leaves.
- Plant anthracnose-resistant species and cultivars. The London plane tree (Platanus acerifolia) cultivar ‘Bloodgood’ is moderately resistant. The oriental hybrids (P. occidentalis x orientalis) ‘Columbia’ and ‘Liberty’ are also resistant.
Chemical Management
IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.
- Apply fungicides when buds swell and when bud caps begin to break.
- Apply again 10-14 days later (a 14-day interval is required for Spectracide IMMUNOX).
- Homeowners should not make foliar applications to trees over 10 ft tall.
- Consult a commercial pesticide applicator for treatment of trees and shrubs over 10 ft. tall.
Approved Pesticides
Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.
Additional Image
Photo by: R.S. Byther