In live oaks , leaves on infected trees show a characteristic pattern. The veins on the leaf will turn yellow or brown, while the rest of the leaf remains green. This very distinctive pattern is called veinal necrosis . While these last two symptoms may indicate oak wilt, they can also be indicators of other problems like herbicide damage. Once symptoms appear, live oaks usually drop their leaves and die over a period of three months to one year.
Some trees can survive for many years in various states of decline.
In red oaks , the time between the first sign of symptoms and tree death occurs much quicker than in live oaks. Red oaks die within several weeks to several months after the first symptoms appear. Leaves begin wilting, and soon after, the tips will begin turning reddish-brown or brown. This will continue until the leaves are entirely brown. Leaf symptoms usually develop on one branch and then quickly spread to the whole tree.