P&PDL Picture of the Week for
May 26, 2008

Sycamore Anthracnose

Gail Ruhl, Sr. Plant Disease Diagnostician, Purdue University

If your lawn is carpeted with leaves from your Sycamore tree, do not despair! The tree is not dying - just experiencing a temporary set-back from infection by a fungal disease known as Sycamore Anthracnose.

Anthracnose is the common name for a type of leaf spot and canker disease caused by certain kinds of fungi. Anthracnose diseases affect many trees, but are particularly prevalent on white oak, ash, maple, walnut and sycamore. Each species of tree is infected by a different species of fungus, thus the fungus does not spread from oak to maple or maple to ash or ash to sycamore. A different fungal species is also responsible for dogwood anthracnose.

Symptoms are especially severe in years with cool, wet spring weather, such as that which we are currently experiencing! The symptoms will vary depending on the type of tree and the stage of plant development at the time of infection: leaf spots or blotches; twig dieback and wilting; and browning or death of emerging leaves are all possible.

Although premature leaf drop often occurs with anthracnose diseases, most of the trees infected with anthracnose usually show good resilience and refoliation, and are not permanently damaged by this early season fungal blight.

For more information refer to Anthracnose of Shade Trees - BP-9-W, Dogwood Anthracnose - BP-48 and Leaf Diseases BP-143.

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Sycamore Anthracnose

Sycamore Anthracnose

Sycamore Anthracnose

Maple Anthracnose

Ash Anthracnose

Purdue Plant & Pest Diagnostic Lab Purdue Cooperative Extension Service