Anthracnose is a disease that can be mistaken as oak wilt easily. One of the easiest ways to distinguish the difference between the two is that oak wilt starts at the top of the canopy and anthracnose starts at the lower and inside of the tree where the humidity is highest. A fungus, Apiognomonia quercinia, causes oak anthracnose. The fungus affects the buds, leaves, or twigs. The leaves may begin to develop brown spots and patches. Some leaves even start to become misshaped. During the winter the fungus lies dormant in the infected leaves, but in the springtime, the spores become airborne and infect the new leaves coming on. Anthracnose thrives in moist and warm conditions and can be spread by watering and rain. The best way to control anthracnose is to rake up the dead, moist leaves during the fall and winter months along with pruning the dead and dying branches.