Scott, Walter E. (ed.) / Wisconsin Academy review
Vol. 3, No. 4 (Fall 1956)
Chambers, E. L.
The Dutch elm disease in Wisconsin, pp. 148-149
148 Wisconsin Academy Review THE DUTCH ELM DISEASE IN WISCONSIN By E. L. Chambers State Entomologist The Dutch elm disease is a relatively new disease of our American elms. It was believed to have been Intro- duced into this country from England on Burl elm veneer logs In 1930. This fatal disease of the elm is caused by a fungus, Ceratostomella ulmi, that gets into the water conducting vessels of the tree and multiplies rapidly and causes the leaves to wilt and the tree to die. It is In- troduced into healthy elms by two species of elm bark beetles feeding on the twigs and small branches. In the past 25 years since its introduction, the di- sease has spread into most of the states east of the Missi- ssippi River and as far south as the states bordering on the Gulf of Mexico. By 1950, it appeared in southern Illi- nois and in five years spread over most of the state. Con- tinuing its pattern of spread of nearly a dozen counties each year, it was not surprising to have it appear in Wis- consin this summer, the first tree being found at Beloit on July 6. Subsequently, it has been found in six counties. By the 15th of September, 52 trees had been diagnosed as being infected with the disease in 15 municipalities. Some 20 municipalities were surveyed street by street under the supervision of the State Entomologist's Office in search of elm trees showing symptoms of the disease. Twigs showing typical discoloration of the wood beneath the bark from more than 600 trees have been cultured. Probably a much AV-eo. Wj4A Seal ler Ero~ecL EI I m. IDI'S Eo.. cq-,S-5 (0 ) / Z A POSITIVE DUTCH ELNv DISEASE SPECIMEN LOCATIONS -- Beloit (2), Delavan (2), Fox Point (1), Glendale (3), Janesville (1), Kenosha (11) Lake Geneva (1), Milwaukee 4), Racine (17), Silver Lake (i) Walworth (1), Waukesha Co. (1), Wauwatosa (5), Williams Bay (IS and West Allis (1). Wisconsin Academy Review 0148
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