Anthracnose Diseases of Shade Trees

Anthracnose diseases occur on many landscape trees; though, in Kentucky, they tend to be most severe on ash, dogwood, maple, oak, and sycamore. They are typically foliar diseases but twigs, branches, and buds may also be affected. Twigs and branches may develop cankers or dead areas that girdle the stem, causing death of distal parts of the stem. Premature leaf drop commonly occurs on infected trees. Anthracnose is not fatal (except for dogwoods in some circumstances); however, severe defoliation from anthracnose year after year can seriously weaken trees. Weakened trees become more susceptible to environmental stresses and secondary pathogens. Dogwood anthracnose or lower branch dieback caused by the fungus Discula destructiva, because of its greater impact, is discussed in U.K. Extension publications ID-67 and PPFS-OR-W-6