Lepidium densiflorum is a species of flowering plant in the mustard family known by the common names common pepperweed and prairie peppergrass.
It is a common and widespread plant in North America, where it grows in many habitats across Canada and the United States.
Lepidium densiflorum is an annual or biennial herb producing a short, erect, branching stem up to about 30 centimeters in height. Leaves grow in a basal rosette at the base of the stem and reach up to about 10 centimeters long; leaves higher up on the stem are smaller and less prominently lobed.
The fruit is a few millimeters long.