Photo of the week: elephant's footprint disease

October 18, 2025

When I visit Japan in the autumn, I'm always on the lookout for elephant's footprint disease in the rough. These patches are about the size of an elephant's footprint. They are caused by Rhizoctonia cerealis, the same pathogen that causes the relatively innocuous yellow patch disease on cool-season grasses from autumn to spring.

In Japan, the disease symptoms occur in tall Zoysia japonica in the autumn as the growth slows and the mowing frequency is decreased.

This doesn't kill the…