Lepidium virginicum

Lepidium virginicum, also known as least pepperwort or Virginia pepperweed, is an herbaceous plant in the mustard family (Brassicaceae). It is native to much of North America, including most of the United States and Mexico and southern regions of Canada, as well as most of Central America. It can be found elsewhere as an introduced species. Virginia pepperweed grows as a weed in most crops and is found in roadsides, landscapes and waste areas. It prefers sunny locales with dry soil....read more on Wikipedia.