Signs and Symptoms:
Though symptoms vary among species of trees, dead areas in the foliage
are common to all affected trees. Anthracnose develops as a light brown
area of circular or irregular dead tissue. Leaves may be stunted in
size. On sycamores, several stages of symptoms appear. The early stage
completely kills young leaves and twigs and may be confused with frost
injury early in the season. The later leaf-blight stage develops as
irregular brown area adjacent to and centering on the midribs and lateral
veins of mature leaves.
Cankers can form which girdle and kill
young twigs. This killing of twigs is followed by rebranchings; sometimes
many new twigs will originate from a single point and result in formation
of a "witch's broom." Anthracnose is most likely to occur
during the spring just after budbreak when moist conditions are present.
Temperatures of 50-55 F are ideal for the fungus to produce spores which
infect newly developing leaves.
Cultural Practices for Control:
Good tree care practices, including fertilization, pruning and watering
during droughts, will reduce stress on the tree and increase its resistance
to infection.
Continued defoliation weakens trees
and often makes them unsightly. If damage occurs year after year, the
trees will need maintenance each year.
Pro Care Practices for Control:
Pro Care tree care services include deep root fertilization, which is
very important for trees prone to anthracnose. Fungicide applications
for anthracnose are not effective because of timing and sporadic budbreak;
they are also very expensive.
The Pro Care staff is always ready to assist you with your trees and
shrubs. Please call if we may provide information to enhance your landscape's
health or appearance.