Diseases of Chestnut Trees

Chestnut trees are stately deciduous trees that grow well in temperate areas of the United States. In the right conditions, they are fairly easy to grow but take nearly 30 years to produce their first crop. To grow your chestnut until it reaches maturity, you will have to keep an eye out for a number of chestnut diseases.

Chestnut Blight

Chestnut blight is a virulent disease caused by the fungus Endothia parasitica which causes cankers on the branches that then spread to the trunk of the tree. There is no cure for chestnut blight, so most of the chestnut trees grown in America today are the Asiatic varieties, which are resistant to the disease.

Twig Canker

Twig canker causes brown discoloration and calluses on chestnut twigs that eventually move to the branches. Affected plant tissue wilts and eventually dies. There is no cure for twig canker, but it largely affects only very young, old or sick trees.

Leaf Spot Disease

Leaf spot is caused by a fungus which mars the chestnut tree's leaves with reddish-brown spots that often have a yellow border. Leaf spot is not a serious disease, and the best remedy for it is to remove all affected foliage to stop the spread of the disease. Throw all pruned foliage away.

Powdery Mildew

Powdery mildew is marked by a white, powder-like growth on the leaves of the chestnut. This mild disease is easily treated with an application of the fungicide benomyl. If you catch powdery mildew early enough, you may be able to control the infestation simply by pruning the affected foliage. However take care not to remove more than one-third of the plant's foliage.

Phytophthora Root Rot

Phytophthora root rot is caused by a soil-born fungus. Chestnut trees affected with root rot feature cracked bark that often weeps sap. Death usually swiftly follows. There is no cure for phytophthora root rot. However, the disease does need water-logged soil to thrive. Improve the drainage and sterilize the soil of the planting area after the tree is removed, or choose another spot for your next chestnut tree.


Anthracnose is caused by the fungus Glomerella cingulata. It causes the veins and stem of the leaf to turn brown before the leaf shrinks and ruptures. Since the fungal spores are produced on the leaves as well as the bark, all infected leaves and the producing twig or branch should be pruned and thrown away. Follow the pruning with an application of lime sulphur while the next crop of leaf buds are still dormant.

Keywords: chestnut blight, chesntut tree disease, chestnut fungus

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Emma Gin is a freelance writer who specializes in green, healthy and smart living. She is currently working on developing a weight-loss website that focuses on community and re-education. Gin is also working on a collection of short stories, because she knows what they say about idle hands.