Wilt diseases are usually responsible for the slow to moderate decline of trees and shrubs. Individual branches may discolor and die. Some wilts may affect only one side of the plant. A common symptom associated with wilt diseases is vascular discoloration (discolored sapwood). Leaf scorch and a reduction in canopy size are additional symptoms. Wilt pathogens may be spread by insects, such as Dutch elm disease spready by elm bark beetles and Bacterial leaf scorch by leaf hoppers. Bacterial leaf scorch is very common on pin oak and others in the red oak family.

Diverse plantings can help prevent the loss of large numbers of trees of the same species. For Dutch elm disease, remove and destroy infected trees to limit the spread of elm bark beetles. Trees of high value may be injected with fungicides by an arborist. To reduce the spread of Verticillium wilt, do not plant susceptible maple trees into infested fields or areas. Replace diseased shade trees with resistant species.

For chemical control recommendations, consult the Insect and Plant Disease Control Manual, UT Extension Publication 1690, found here. Please contact your local Extension office for specific pesticide recommendations.