The purple-brown spots on maple tree leaves indicate development of fungus and this can cause problems for your cherished tree. The present article deals with maple tree diseases caused by fungi. Read on, to know how to take care of the tree that helps enhance the beauty of your garden.
Maple trees grow mostly in the North Temperate Zone and are very common in the United States. The size of the tree varies according to the species. Some are small, about fifteen to twenty feet in height while some grow to seventy feet or more in height. These are deciduous trees and propagate by seeds. The palm shaped leaves which are veined and lobed in green, red, orange and yellow hues, enhance the beauty of the tree. The leaves turn scarlet red in the fall and have a startling effect on the beholder.
Fungus on Maple Trees
Different types of fungi attack maple trees. Fungi do not have chlorophyll and they derive nourishment by feeding on trees. Fungi are mostly microscopic; but some are visible, for instance, mushrooms or conks. Fungi are responsible for the most common tree diseases. Bacteria and viruses also can affect the growth and life of a tree.
Sooty Mold Tree Disease
Any tree can be a victim of sooty mold disease but this disease is most commonly seen on boxelder, elm, linden, and maple. The pathogens are dark fungi, which are common on maple trees. The honeydew excreted by sucking insects provides them the required nourishment. They can also get nourishment from exuded material coming from the leaves of the trees.
Anthracnose
Anthracnose is scientifically recognized as Colletotrichum spp. This class of diseases includes three diseases caused by fungi. These fungi affect the leaves and branches of the tree. Purple brown spots along the veins and dark brown spots between or along the veins of the maple leaves indicate occurrence of the disease. You can see several small spots on the leaves and cankers on the branches. The trees are more likely to suffer from the disease, in the prolonged cold and moist weather. These fungi can damage the buds, twigs and can lead to an untimely fall of the maple leaves. A prolonged wet spring serves as a perfect breeding platform for the spores. Removal of the affected leaves, twigs and branches is necessary to get rid of the fungi. You should consult an expert before using a fungicide.
Tar Spot
The fungus responsible for the tar spots on the leaves of the tree is the most harmless maple tree fungus. It belongs to the genus Rhytisma. Tar spots on the maple leaves develop as a small yellow spot and turn black afterwards. Their diameter can be about an inch or more; and they can be found on the seeds (samaras) too. The pathogenic fungus is responsible for the untimely fall of the leaves. It can be easily identified. Although the disease does not cause serious consequences to the health of the tree, it destroys the beautiful look of the tree. Such tar spots are common on Norway maple, Silver maple and Sugar maple. Since the disease affects the upper surface of the leaves in spring, it generally results in the falling of leaves, before fall. Tar spot is not a serious problem and so no treatment is recommended.
Maple Wilt
Maple wilt, also known as Verticillium Wilt, is the most grave disease for the tree. The soil borne fungus called Verticillium, plays an important role in killing several maple trees. The disease caused by the fungus destroys the vascular system of the tree and eventually kills the tree. The disease is difficult to prevent because there are no significant symptoms of the presence of the fungus in the soil. This fungus attacks the tree through the roots. The fungus can be present in the soil for years before the symptoms appear. When the situation is worsened, the leaves of the affected trees appear brown or yellow and the color of the sapwood turns olive. Cutting off the tree to avoid the spread of the disease to the other maple trees in the area, is the only solution to this disease. This disease has the capacity to destroy a fully grown tree. Norway maples are most susceptible to maple wilt. Sugar maple, Japanese maple and Silver maple are the other common species that are more affected by this disease.
Sapstreak
Sugar maples are affected by the sapstreak disease. It is caused by the fungus Ceratocystis coerulescens. The fungus has the power to cause serious damage to the sugar maple. In the early stages, the disease may not appear serious, but if its growth is not restricted or stopped, it can cause a serious threat to the tree. The fungus destroys the quality of the wood. The maple wood fades due to the fungal attack. The tree is not useful for lumber, if it is affected by this disease. The leaves at the top of the tree become smaller. You can easily detect the bald spots. The process of dwarfing continues and eventually the tree dies. Cutting down the tree is the only solution as nothing can cure the disease. Phytophthora Root Rot can kill the maple tree in a similar way.
There exist numerous types of maple trees and all can be used for landscaping. The wood of the tree is an excellent source of fuel. High quality charcoal is made from the wood. The wood is also known for its ornamental quality. The fine-grained wood is used to make sturdy furniture. The trees have a sap that can be converted into sugar easily. They are used as lumber for construction.
Pests, insects, and fungus can bother the tree. Maple tree diseases need prompt treatment. Each type of maple tree requires different soil and climate conditions. To avoid the diseases, you should use appropriate soil for tree planting.
As the diseases can kill your precious tree, taking good care of the tree, before the fungi can lead to a deadly disease, is extremely important. Regular and sufficient supply of water, fertilizers, and pesticides, providing perfect soil, cleaning the area around the tree promptly, pruning the tree periodically, everything is equally important for healthy growth of the tree. If you notice that your favorite maple tree is looking ill, or if you notice any kind of infection, you should immediately consult an expert.