Anthracnose is a fungal disease that affects trees and plants all over North America, including here in Ontario. It thrives in moist conditions, particularly during the rainy months of spring or humid weather in the summer. It can survive on plant debris through the winter and resurface on plants in the spring. There are some anthracnose treatments and methods for prevention available.
Anthracnose typically affects ash, maple, and oak varieties of trees, although other deciduous and evergreen species can get infected. It can spread through contact with plant debris, wind, rain, insects, and even gardening tools. Typically, it is not fatal to trees but can be fatal to plants and other crops.
What Does Anthracnose Look Like?
Anthracnose generally prevents trees from budding as early as expected. The tree will likely not have leaves until late June or early July and will fall earlier than usually in the autumn.
Once the tree buds, the leaves will have dry brown and black lesions that begin to form on the edge of the leaves, but slowly will spread to the whole leaf. It can also kill the tips of twigs and in some cases, cause defoliation of the tree.
Anthracnose Treatment and Control
The best way to control and prevent anthracnose in trees is to rake up your leaves from your yard and put them out for yard waste in the autumn. This prevents the return of the disease to trees and new leaves in the following spring.
Removing plants that are infected with the disease will help prevent the spread to other plants. With trees, however, completely removal is not usually necessary or recommended. Pruning out the dead leaves and twigs as well as removing all leaf and plant debris from around the base of the tree.
While anthracnose is not usually fatal to trees, if there is a lot of twig and leaf damage, it can make the tree susceptible to other diseases or cause the tree to become further unhealthy.
If you believe your tree could be infected with anthracnose or another disease, call P & A for an assessment. We can discuss anthracnose treatment options and ways to keep the rest of your trees healthy.