Spring Showers: More Oak Wilt?

Apr 24, 2013

Austin live oaks have benefited from recent rains, but that rain could also put them at risk for oak wilt, a fungus that spreads quickly through trees’ root systems and can kill them in as little as six weeks. 

Chris Dolan, head of oak wilt prevention for the City of Austin Arborist’s office, said oak wilt enters a tree through open wounds from pruning and forms “fungal mats,” which infect trees and make them susceptible to parasites.

“We should see more active oak wilt, and I haven’t seen a fungal mat in two or three years,” Dolan said. “So I am expecting some. In my conversations with the foresters at the Texas Forest Service, they believe we’ll see some fungal mat.”

Dolan said that drier conditions over the past three years have abated oak wilt because with less water, fungal spores move less efficiently through root systems connecting swaths of trees.   

He said live oaks are more likely to get oak wilt than red oaks and die quicker after oak wilt sets in.

People with oak trees should avoid pruning until June, but Dolan advises sealing wounds on the tree after pruning year-round.