We normally expect trees to experience some leaf fall, especially during the autumn months. A few trees also have a tendency to shed some leaves in spring after keeping those leaves during winter. But when a large number of leaves become discoloured and start dropping regularly in springtime, your tree needs attention and care. It may be suffering from a disease called Anthracnose.
What is Anthracnose?
Anthracnose is a disease caused by the fungus Gnomonia. Oak, dogwood, sycamore, ash, elm, and maple trees are most vulnerable to it. Of all the diseases that attack hardwood trees, anthracnose is one of the most noticeable, but it does not harm the tree as much as some others.
Fungal spores start infecting twigs and leaves during the winter, and cold, wet weather encourages the development of the disease. When spring comes, the spores spread and contaminate new buds and shoots.
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Signs
On leaves, brown or reddish discolouration will start to appear, especially on the veins and edges. At first, the leaf becomes deformed but stays fastened on the branch. As the disease progresses, it will cause the entire leaf to wither and drop. With many leaves dropping, the tree loses a good amount of foliage.
On twigs or branches, the discolouration will initially look like a moist area, then later turns brown. The bark decays, crumbles and peels off. Fruit and flowers may also be affected.
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Prevention
Regularly rake and dispose of leaves that have fallen on the ground. Inspect the trunk and branches and prune when necessary to remove infected areas. To protect your tree from disease, boost its health with fertilizer and water it regularly.
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Action
Continue to water and fertilize your tree so it can produce new leaves. Don’t water the leaves directly, though, so they can dry. Pruning is also essential to increase the flow of air between the leaves and branches, and let in more sunlight.
Mature trees can often recover from this infection but younger trees may be permanently damaged. If the infection occurs repeatedly and is left untreated, the tree may begin to deteriorate and become an easy target for pests. In this case, definitely seek help from professional arborists.
Most tree problems can be avoided. Be aware of pests and diseases such as anthracnose to keep your tree in the best of health.
For more advice on tree care, contact the specialists at Caledon Treeland in Toronto. We offer a variety of robust trees to enhance your landscape. Give us a call at (905) 880-1828.