Perilla frutescens is an erect, annual freely branching herbaceous plant that grows from 1-6.6 ft. (0.3-2 m) tall. The square stems are villose, purple or green with four parallel grooves. Dried stalks can persist through winter. It is native to Eastern Asia.
Foliage
Opposite leaves are membranous or herbaceous, broadly ovate or orbicular, 2.76-5.12 in. long by 1.77-3.94 in. wide (7-13 cm X 4.5-10 cm), with mucronate tips, a rounded or broad cuneate bases, and dentate margins. The pilose surface of the leaves may be green or purple on both sides. Each leaf has seven to eight pairs of lateral veins, which are closer together near the base. The veins on the upper surface are slightly raised, more so on the underside. The petiole is flat and villose.
Flowers
Flowers are held in pairs along the stalk. The inflorescence is a villose corymb that may grow either terminally or from the leaf axils.
Fruit
The sub-globose fruits are reticulate nutlets, grayish-brown, and are about 0.06 in. (1.5 mm) in diameter.
Ecological Threat
P. frutescens grows along roadsides, ditches, forest margins, and on hillsides. It spreads to natural areas, especially disturbed areas. I can disrupt native ecosystems by outcompeting native plants. It is ordinarily avoided by cattle and has been implicated in cattle poisoning. Beefsteak plants are most toxic if cut and dried for hay late in the summer, during seed production.