Signs of Japanese Maple Disease

Japanese Maple trees are wonderful additions to your yard. Their attractive foliage adds beautiful color to your landscape and compliments other plantings. However, Japanese Maples are susceptible to quite a few pests and diseases. Here are a few symptoms of ailments that may affect your trees, along with some tips for good Japanese Maple care to keep your trees healthy.

• Tree is not growing well: There are a couple of things to look for if your tree is growing poorly. First, is it planted near a black walnut? If so, it needs to be moved, as black walnut trees are toxic to some other types of trees, including Japanese Maple. The other problem causing poor growth is root girdling, when the smaller roots of the tree grow onto the larger roots, choking out nutrients. This can be remedied by cutting the smaller roots.
• Wrinkled, wilted leaves: This is usually a sign of aphids. If you look closely, you may see small green insects on the leaves, or you may see the sticky honeydew they leave behind. Aphids can be controlled with an insecticide, or by introducing a natural predator, such as ladybugs.
• Yellow or brown wilting leaves: If you notice this symptom in your Japanese Maple leaves, it is likely that your tree is affected by Verticillium Wilt, a fungal disease common to maples. You may even notice entire branches dying off. Prune out the affected branches, and fertilize with a high-nitrogen fertilizer.
• Lesions on branches and trunk: These lesions, called cankers, are caused by fungal infection. Left untreated, the tree will die. At the first sign of infection, prune out all affected branches. Prevention is key when it comes to canker disease. Try to prevent injury to the trunk bark to keep fungus from getting into the tree.
• Reddish-brown lesions on leaves: These lesions will often spread and cause the leaves to die off. Gather and discard affected leaves, and feed and water the tree. Severe cases may require the use of a fungicide.

While Japanese Maple trees do require a little more care and attention, their lovely shape and color make these beautiful trees worth the extra effort needed to keep them healthy.