Sycamore Anthracnose
Apiognomonia veneta (syn. Gnomonia platani)
4 host plants
Last updated
This profile synthesizes data from multiple published sources. Expert field review is in progress.
Sycamore anthracnose causes leaf spotting and defoliation on sycamores and European maple, with symptoms most severe following cool, wet springs. You'll notice brown patches on expanding leaves, sometimes with a target or concentric pattern, and affected leaves may drop prematurely. The disease can affect new shoots and twigs as well, creating a blighted appearance on developing growth.
Healthy trees tolerate anthracnose better than stressed ones, so your management goal is keeping trees vigorous. Rake and destroy fallen leaves to reduce overwintering fungal structures, and consider planting resistant varieties like Bloodgood plane tree or the oriental hybrid cultivars Columbia and Liberty if anthracnose has been a consistent problem on your property. Cultural care, good drainage, and proper pruning will help trees recover from leaf loss faster.
Quick Reference
Management
Spring (April-May) during bud swell and young leaf emergence (BBCH 08-16). Peak: late April through mid-May. New foliage most susceptible.
Cool wet spring (50-57°F) with 12+ hours continuous leaf wetness during bud break and young leaf development. Rain-splash dispersal.
Cultural Controls
- Provide proper culture to maintain tree health.
- Healthy trees are more tolerant of leaf loss and recover more quickly.
- Rake and destroy fallen leaves in fall.
- Plant anthracnose-resistant species and cultivars.
- London plane cultivar 'Bloodgood' is moderately resistant.
- Oriental hybrids (P. occidentalis x orientalis) 'Columbia' and 'Liberty' are also resistant.