Also known as mercuryweed, threeseeded mercury, and wax balls, this summer annual is a member of the spurge family, Euphorbiaceae, that also includes poinsettia , croton, and caster oil plant.…
Common knotweed is an annual weed and a member of the buckwheat family, Polygonaceae, that also includes rhubarb, sorrel, and dock. It is native to Europe and Eurasia but was…
Russian knapweed is a woody , rhizomatous perennial and member of the aster family, Asteraceae, that also includes sunflower, yarrow, and lettuce. It is native to Eurasia but was introduced…
The fungus-like water mold, Phytophthora infestans, causes late blight in tomatoes and potatoes as well as in some other members of the nightshade family, Solonaceae. It appears first as dark…
Similar to Stewart’s wilt, this bacterial disease has two phases. The first appears early in the season and is characterized by orange to brown discoloration of diseased vascular tissues and…
Caused by the fungus Ustilago maydis, this disease can affect all above ground parts of the plant but is most economically significant when it attacks the ears. It causes the…
Northern corn leaf blight is caused by the fungus Exserohilum turcicum, and first appears on the lower blades at the time of silking or at full maturity It is characterized…
Caused by the bacterium, Pantoea stewartii, Stewart’s wilt has two phases. The first affects seedlings that may develop linear pale green to yellow streaks, wilt and dry up. The second…
Angular leaf spot is a bacterial disease affecting cucumber and other cucurbits, including squash, pumpkin, and melon. The infection begins with small, angular, brown to straw-colored water soaked spots on…
The most common corn rust is caused by the fungus Puccinia sorghi and usually appears after tasseling as dark, reddish-brown pustules on the upper and lower surfaces of the leaves.…
Karen 
Karen Meyers