Strains of hoary cress, particularly within the lens-podded species (Cardaria chalepensis (L.) Hand.-Maz.), varied greatly in leaf size and shape, spreading ability, stand density, and reaction to treatment with several herbicides. Without competition, heart-podded hoary cress (C. draba (L.) Desv.) spread farther and produced a denser stand than either lens-podded or globe-podded cress (C. pubescens (K. A. Meyer) Jarm.), and, in general, was more susceptible to 2,4-dichlorophenoxyacetic acid (2,4-D) and trichlorobenzoic acid (2,3,6-TBA) than lens-podded cress. Within 12 strains of lens-podded hoary cress no relationship was found between susceptibility to 2,4-D or 2,3,6-TBA and any other characteristic.