Weed of the Month: Johnsongrass

In January, the Minnesota Department of Agriculture (MDA) added Johnsongrass (Sorghum halepense) to the Prohibited Eradicate Noxious Weed List. Johnsongrass is a tall perennial grass that grows up to eight feet and can cause millions of dollars of lost agricultural revenue. It was first introduced into the United States as a forage crop in the early 1800s.

Johnsongrass prefers full sun and disturbed soil and can tolerate a variety of habitats. Johnsongrass grows in pastures, roadsides, ditches, abandoned lots, and waste areas. It spreads vegetatively by rhizomes, growing vigorously up to 60 feet in a single year. It produces large quantities of seed that are moved by humans, animals, and water.