Plant Diseases

Dutch Elm Disease

Dutch Elm Disease
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Bonide Solutions:
The tall, stately elms once graced American streets have been devastated by this fungus disease. The "Dutch" in the name refers to the nationality of the botanist who discovered the fungus. For years confined to the East and Midwest, the disease spread slowly across the country, reaching the West in the 1970s.
Dutch elm disease kills by clogging a tree's water conducting tissue. It's transmitted by the elm bark beetle, and can also move from infected trees to nearby healthy ones when the roots rub against each other, Chinese, Siberian, and a few other Asian elm species are not susceptible, and plant breeders are working to develop new resistant varieties with the majestic shape of the American elm.

Target: American and European elms.

Damage: The leaves of one or several branches wilt, turn yellow, and drop; then the wood, and eventually the entire tree, dies as well.

Control: Resistant varieties, controlling bark beetles, proper pruning.

Notes: Maintaining a healthy tree is the best way to discourage bark beetles.
Once a tree is infected, there’s no cure.
Remove and destroy diseased wood to keep the fungus from spreading.