Plant Disease Management Handbook

Verticillium Wilt in the Pacific Northwest

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Verticillium wilt symptoms can include wilt (top left and top right) chlorosis (top right and bottom left) and reddish to purplish discoloration of leaves or stems (bottom left) and distorted or stunted leaves (bottom left and right).
Photos courtesy of Jerry E. Weiland (USDA-ARS) and Dennis A. Johnson (Washington State University).
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Verticillium wilt symptoms can include wilting and chlorosis as seen in this Cercis canadensis tree.

Jerry Weiland (USDA-ARS)
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Symptoms of Verticillium wilt often occur on one side of a plant or leaf, as seen here with infected potato (left) and black raspberry (right).
Photos courtesy of Jeremiah Dung (Oregon State University) and Jerry Weiland (USDA-ARS).
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Symptoms of Verticillium wilt often occur on one side of a plant or leaf, as seen here with infected black raspberry.
Jerry Weiland (USDA-ARS)
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Severe and extensive Verticillium wilt damage in a perennial field of peppermint.
Photo courtesy of Dennis A. Johnson (Washington State University).
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Premature fall coloration of Japanese maple (left) and red maple (right) caused by Verticillium wilt.
Photos courtesy of Jerry E. Weiland (USDA-ARS).
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Branch dieback and death in vine maple (left), black maple (center) and Norway maple (right) caused by Verticillium wilt.
Photos courtesy of Jerry E. Weiland (USDA-ARS).
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Vascular discoloration of smokebush caused by Verticillium wilt. Note how the discoloration appears as a circular or semicircular pattern in cross section.
Jerry Weiland (USDA-ARS)
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Vascular discoloration of sugar maple caused by Verticillium wilt. Note how the discoloration occurs along the direction of the grain.
Jerry Weiland (USDA-ARS)
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Vascular discoloration of vine maple (bottom right) caused by Verticillium wilt. Note how the discoloration occurs along the direction of the grain and appears as a circular or semicircular pattern in cross section.
Jerry Weiland (USDA-ARS)
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Damping-off in Tree Nurseries

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Douglas-fir seedling wilting due to infection with Pythium irregulare.

Jerry Weiland, 2012.
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Douglas-fir seedling with with Pythium irregulare - healthy plant on left, 3 diseased plants on right.

Jerry Weiland, 2012.
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Fusarium stem canker on these sugar pine seedlings.

OSU Plant Clinic collection, 2012.
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Disease and weed pressure in nonfumigated plot (top right side image and foreground bottom image right) compared to fumigated plot (top left side and bottom image background). Same seed lot for both plots.

Jerry Weiland, 2012.
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