Description: Beefsteak plant is a small, annual herb in the mint family. This invasive grows between 18 and 30 inches. Leaves are ovate, opposite, and purple or green in color. Beefsteak plants have small white or purple bell-shaped flowers. These flowers appear between July and October in terminal clusters or within the leaf axils. The stems and leaves of beefsteak plants have a strong odor.
Ecological Threat: This invasive is traditionally planted as an ornamental, but can escape and disrupt native ecosystems. These plants easily spread to disturbed areas. This invasive species is poisonous to cattle and has very few predators. Because cattle avoid this plant it has a competitive advantage to native plants eaten by herbivores.
Biology & Spread: Beefsteak plants have windborne seeds that allow wide dispersal.
Threat in Oklahoma: This plant is toxic to cattle, is easily dispersed by Oklahoma wind, and has the ability to outcompete native flora.
Image Credit: Jil Swearingen, USDI National Park Service, Bugwood.org - See more at: http://www.invasive.org/browse/detail.cfm?imgnum=0581033#sthash.WXNSbrah.dpuf
Center for Aquatic and Invasive Plants