Mustard, BLACK

Bra ica nigra. Yellow-flowered herb of the natural family Crucifer a, native of the Old World, but widely dispersed in America as a weed or by cultivation. It becomes a bad weed in cultivated crops, especially barley, oats, and clover. It is an annual, but the seed retains its vitality so long in the ground that it is very difficult to clean land which has become infested. The seeds of the black and of the white mustard are ground as a condiment and are often adulterated with wheaten flour. Mustard, HEDGE. Plants of the genus Sisymbrium , especially S. of ficin ale , a yellow-flowered weed of the Mustard family, native of Europe, introduced into N. America.