Symptoms vary depending on the oak species involved. The leaves curl slightly and turn a dull pale green, bronze, or tan, starting at the margins. Usually, by late summer, an infected tree has dropped all of its leaves. We have seen red oaks move through initial symptoms to total defoliation in as little as three weeks. The white and bur oak group generally shows symptoms on scattered branches of the crown.
Leaves become light brown or straw-colored from the leaf tip toward the base.
The leaves curl and remain attached to the branches. This tree group may die in one season, but trees are much more likely to survive for many years with a stag-headed appearance. Recent appearances of anthracnose on white oak have caused concern among many tree specialists who fear oak wilt. Anthracnose causes brown spotting scattered over the leaves and may cause slight leaf cupping as well. Other problems, including construction damage, soil compaction, changes in the soil grade or water table, lightning damage, nutritional disorders, insect and animal injuries, chemical damage, cankers, and root decay, can mimic oak wilt.