Just wondering, what is the longevity of oak wilt?

Tree Dude

http://www.dirtdoctor.com/Oak-Wilt_vq285.htm

Good question. Since it spreads through the root zone it seems like it could linger underground for quite a long time. But that is just a guess. You should call in and ask, I suspect a lot of people wonder if they can replant oaks again any time soon after losing trees to the disease.