Anthracnose on a sycamore is treated by spraying a copper-based fungicide at bud break, combined with pruning out any dead twigs and cankered branches from the previous season, since sycamores tend to show a more severe form of this disease than many other trees.

How Does Anthracnose Look Different on a Sycamore Than on Other Trees?

Sycamores are especially prone to shoot blight, the sudden wilting and dieback of new spring shoots, along with cankers, sunken dead lesions in the bark, on twigs and small branches, rather than just the light leaf spotting anthracnose causes on many other species. This more severe presentation tends to show up during cool, wet spring weather, matching TreeHelp's own description of the disease's more damaging canker form, which disrupts a tree's vascular system rather than staying limited to the leaf surface.

What's the Best Fungicide for Treating Anthracnose on a Sycamore?

Spraying Liquid Copper Fungicide Spray onto the tree, at one gallon of solution per 200 square feet or up to two gallons for a large tree, controls anthracnose on sycamores specifically, since both the disease and the species appear on the product's own label. Reapplying every 7 to 14 days, sooner after heavy rain, keeps new shoots protected through the wet spring window when shoot blight is most likely to develop.

When Should a Sycamore Be Sprayed for Anthracnose?

Spraying at bud break, before new shoots have fully emerged, protects them during the exact period when cool, wet weather makes shoot blight most likely. Waiting until wilted shoots or twig cankers are already visible means the fungicide can only protect what grows afterward, not reverse damage already done.

Does Pruning Help Control Anthracnose on a Sycamore?

Removing dead twigs and cankered branches from the previous season reduces how much fungus survives to reinfect new growth. Combined with raking up fallen leaves in autumn, since spores can overwinter in leaf litter beneath the tree, this sanitation step lowers the amount of fungus available to spread the following spring.

Frequently Asked Questions

Can anthracnose kill a mature sycamore?

Rarely on its own. A single season of shoot blight typically doesn't kill a mature tree, though repeated severe infections year after year can weaken its overall vigor over time.

Does sycamore anthracnose look like frost damage?

Yes, often. The sudden wilting of new shoots can closely resemble a late frost injury, which is part of why the disease sometimes goes misdiagnosed until cankers or repeated dieback make the actual cause clearer.

Is sycamore anthracnose contagious to nearby trees?

Yes. Like other forms of anthracnose, it spreads through spores carried by wind and rain, so a heavily infected sycamore can pass the disease to other susceptible trees nearby.

Should fallen sycamore leaves be raked up in fall?

Yes. Removing fallen leaves reduces the number of spores that would otherwise overwinter on the ground and reinfect the tree's new shoots the following spring.