First Spotted in Eastern New York

• Oak wilt was first identified in Wisconsin in 1944. Oak wilt is considered a native disease, since the fungus has never been reported by any other countries. Oak wilt was first spotted on New York trees in Schenectady County in 2008.
  
  

Spread Via Roots and Pests

• Oak wilt is spread from tree to tree either by the infected tree's underground root system or grafting (called "local spread"), or by pests that carry fungal spores as they travel across areas (called "overland spread"). The oak wilt spore excretes a fruity odor that attracts insect pests, in particular the nitidulid beetle and oak bark beetle.
  
  

Symptoms of Infection

• An infected tree shows immediate symptoms in its foliage: the leaves are discolored, first a washed-out green color that turns bronzed. The tree's leaves wilt and fall, from the crown of the tree downward. The bark of tree may show faint brownish-colored streaks or flecks. Infected trees, particularly red oaks, can die within three weeks.
  
  

Treatment and Removal of Infected Trees

• Trees suffering from oak wilt are usually cut down and the stumps treated with herbicide. To control the spread and prevent massive infestation, quick identification and removal of infected trees is crucial in the fight against oak wilt.
  
  

Preventing Oak Wilt

• Cornell University Extension recommends homeowners not prune oaks in the spring, between April 15 and July 15 in New York State. Insects that spread oak wilt visit new wounds on trees and can infect newly pruned trees.