This fallen leaf has galls all over it, lumps or complicated structures that look like capsules containing something mysterious. Galls are made by one of 1500 species of gall producers -- mostly insects and mites. Some galls form on leaves where insects feed on the plant matter, or lay eggs. Galls may also develop as a response to infections by fungi, bacteria, or viruses. Dissecting the gall is the only sure way to tell what caused it. That's a whole different adventure!
