Trees and Diseases

Turf isn’t the only plant material diseases love to attack when the conditions are just right; trees are also susceptible to disease outbreaks. Here is some background on common tree diseases. Lawn care operators should keep this information on hand in order to identify tree-specific diseases in their clients’ landscapes and treat them with the appropriate method, including microinjection and soil treatments. 

American Chestnut Blight: A fungus that has virtually wiped out the American chestnut, as a commercial species, from eastern hardwood forests.

Annosus Root Rot: A rot of conifers in many temperate parts of the world.

Anthracnose Diseases: Particularly severe on American sycamore, white oak, black walnut and dogwood trees.

Armillaria Root Disease: Attacks hardwoods and softwoods and kills shrubs and vines in every state.

Beech Bark Disease: Causes significant mortality and defect in American beech; results when bark is invaded and killed by fungi.

Brown-Spot Needle Blight: Delays growth and causes mortality of longleaf pine.

Cankers on Western Quaking Aspen: An aggressive pioneer species that frequently colonizes burned sites, making it an important component of many western ecosystems.

Canker-Rot: Fungi that causes serious decline in southern hardwoods, especially the red oaks.

Comandra Blister Rust: A disease of hard pines that is caused by a fungus growing in the inner bark.

Diplodia Blight of Pines: Attacks pines and is most damaging to plantings of both exotic and native pine species in 30 eastern and central states.

Dogwood Anthracnose: Infection of dogwoods is favored by cool, wet spring and fall weather, but can occur throughout the growing season.

Dothistroma Needle Blight: A devastating foliar disease of a wide range of pine species.

Dutch Elm Disease: Primarily affects American and European species of elms; economic loss resulting from death of high value urban trees.

Eastern Dwarf Mistletoe: Is the major cause of death in black spruce.

Fusiform Rust: Causes death within five years of a tree’s life if a stem infection occurs.

Littleleaf Disease: The most serious disease of shortleaf pine in the Southern United States; affected trees have reduced growth rates and usually die within six years.

Lucidus Root and Butt Rot: One of the most common root and butt rots of southern hardwoods.

Oak Wilt: A disease that affects oaks, especially red oaks, white oaks and live oaks.

Scleroderris Canker: Has caused extensive mortality in conifer plantations and forest nurseries in the northeast and north central United States and eastern Canada.

Sirococcus Shoot Blight: Affects conifers in the northern United States and southern Canada.

Sudden Oak Death: Occurs in forests in California and Oregon.

Walnut Anthracnose: A widespread and destructive disease of walnut species, particularly the eastern black walnut.

White Pine Blister Rust: Attacks pines with five needles per fascicle, including Eastern and Western white pine, sugar pine and limber pine.

 – The Forest Insect and Disease Leaflet Series, USDA Forest Service