Medusahead ranges in height from 20 to 60 centimeters. It has slender, weak stems that often branch at the base. It has spike inflorescences similar to those of wheat or rye. The lemmas have long awns and the glumes have shorter ones, giving the seed head a layered look. As the awns dry, they twist and spread in all directions, similar to the snake-covered head of the mythological Medusa. The barbs on the awns help the seed drive into the soil. The grainlike seed may remain viable in the soil for a number of years.