Learn how to recognize and treat common maple tree diseases.
Growing maple trees can lead to the sweet reward of making your own maple syrup. Mapping your maple trees, tapping them for syrup and making homemade maple syrup are part of maple syruping. However, it’s also important to properly care for your maple trees. Maple trees can become susceptible to pests and diseases. Learn the warning signs of maple tree diseases and what you can do to take the best care of your maple trees.
Most Common Maple Tree Diseases
Tar spot is a fungal disease that affects the leaves of a maple tree. It’s easy to recognize by the large black spots that look like tar on the leaves. While the disease is pretty harmless, it makes for some ugly leaves. The infection begins in early spring and can continue into the early summer. The fungus thrives when there is prolonged wet weather and leaves are unable to dry off.
Raking up dead, fallen leaves around your maple trees is the only preventive measure you can take.
Maple wilt is one of the more serious maple tree diseases. Leaves will look scorched or have a slight browning. Branches with maple wilt will also have a small amount of the scorched leaves. Maple wilt begins in the root system and spreads through the sapwood, moving up the tree into the upper branches. You can check the sapwood of your tree for olive-colored streaks, a sign of maple wilt. It’s a good idea to consult with your local county extension office. They can assist you in confirming if your tree is suffering from maple wilt.
While a very healthy tree can overcome maple wilt, most trees will die within one to two years of shown symptoms. To control the spread of maple wilt, you’ll need to destroy the infected tree. If the tree is not seriously infected, you can try pruning the infected branches.
Anthracnose is another fungal disease which affects the leaves of a maple tree. The airborne fungus is common after wet, cool winters. It can cause stunted bud formation, kill leaves and cause early leaf loss. You can recognize this maple tree disease by purplish-brown or brown spots along the leaf veins. The disease mostly shows up in April and May. You can help to prevent anthracnose by raking up leaves every fall. The disease thrives in fallen leaves. You can also consult with an arborist about a fungicide treatment.
Sugar maples can be affected by sapstreak. This fatal fungal disease causes the foliage at the tree’s crown to shrink. The disease spreads throughout the tree, ultimately dwarfing the tree and killing it. To rid your maple trees of sapstreak, you’ll have to cut down the infected tree. Insects can help spread the disease, so you need to remove the tree to keep your other maples from becoming infected. Once the tree is removed, you’ll be able to see the recognizable sapstreak pattern in the cut wood.
Preventing Maple Tree Diseases
There are a few ways you can try to prevent maple tree diseases. Fallen leaves are a common breeding ground for maple tree diseases. Raking up dead leaves is an easy way to keep your maple trees healthy. Pruning your maple trees will also help prevent maple tree diseases. Prune your maple trees in the colder months, during their dormant season. Pruning also promotes growth, giving your trees a longer life, improving their structure.
Following a steady regimen of watering and fertilizing is another easy way to keep your maple trees healthy. If you’re ever unsure about the health of your maple trees, consult with an experienced arborist. For more information about maple trees, visit our maple syruping blog.