Tree and Shrub: Anthracnose

Tree and Shrub Disease

Anthracnose affects a wide variety of deciduous trees and shrubs; infecting stems, branches, leaves and/or fruit of the plant. Symptoms can include: necrotic spots, irregular dead blotches or necrotic lesions on the leaf of the plant, defoliation early in the season with new growth in early summer, twig lesions or cankers on branches. Anthracnose can weaken the plant and leave it susceptible to other diseases or insect damage. It is recommended to destroy leaves that have fallen or infected branches to help keep this disease from spreading. Cankers may form on the areas of the tree that dieback occurred which may kill entire branches with girdling.

Cool, moist weather and prolonged winter-like conditions allow for the tree to remain dormant while the disease continues to grow and spreads through air currents or rain. The first treatment for controlling Anthracnose should be made in early spring.

Although Anthracnose affects many deciduous trees and shrubs, the symptoms are similar. Look for blotches of brown or tan along the margin or vein of the leaf, depending on the plant infected the discolored areas may range from small spots to large irregular patterns across the leaf. Some trees and shrubs will drop their leaves prematurely, others may fully defoliate.

It is important for homeowners or property managers to destroy the infected twigs, leaves and/or branches from the plant to help keep the disease from spreading. Often times, this alone may be the only control measure that needs to occur to get Anthracnose in check.

Disease Development Favored by: The disease spores remain inactive in infected leaf debris, twigs, cankers and branches until conditions are met for the fungus to spread. Cool, moist conditions are ideal for the spreading of Anthracnose Corrective Measures: Proper pruning, watering and maintenance to help keep the plant healthy Controlling insects to reduce stresses Proper tree/shrub fertilization to promote health and recovery Thin out areas of the tree to promote air circulation and sun penetration
	Maple
	Ash
	Oak
	Sycamore