Details and Information

Common Names

Insane root, stinking nightshade, fetid nightshade, hog’s beam


Black henbane is an annual or biennial plant that grows up to 3 feet tall. The entire plant is covered with greasy hairs. The leaves are up to 8 inches long and 6 inches wide, and are shallowly lobed, and heavy scented. Flowers are born on spikes and form the leaf axils from May until September. They are showy, 5 lobed, up to 2 inches across, and greenish-yellow in color with deep purple veins and throats. The calyx forms a 1-inch, urn-shaped "fruit" that has a thickened lid that pops off at maturity and spills the black seeds. 

Key Features

Black henbane has large irregular lobed leaves. This plant produces a foul smell. Another feature is the sticky hairs and also the purple-veined yellowish flowers in one-sided spikes. 


Black henbane can be in forage crops, rangeland, irrigation areas, right of ways, and waste areas. 


Herbicides that control Black henbane are Escort and Tordon. Hand pulling and digging is also effective if done before seed production - pull or dig the root. For more information and mixing instructions on herbicides, read the labels or contact the Weed and Pest office. 

Other Facts

Livestock will avoid foraging on Black henbane unless there is no other forage available and can be toxic to livestock if grazed. One single plant can produce up to a half a million seeds. Black henbane alkaloids have been used in the past, and are currently used, in medicines at controlled dosages. Black henbane is poisonous to humans. Tropane alkaloids are found in all parts of the plant.