Several shade tree species are susceptible to Verticillium wilt.
Maples are quite susceptible.
Ash, catalpa, golden rain tree, smoke tree, magnolia, and redbud, and others can also be affected. Susceptible shrubs include barberry, boxwood, dogwood, lilac, spirea, weigela and viburnum. Verticillium is not extremely aggressive but can be a problem on stressed trees and shrubs. Samples that have tested positive for the disease in the Plant Disease Clinic this year include green ash, maple, and catalpa. The fungus Verticillium is found in the soil.