Eragrostis cilianensis

Stinkgrass infestation
Stinkgrass infestation. Photo courtesy Steve Dewey. Licensed under CC BY 3.0.
Stinkgrass is a summer annual grass that grows 1 to 2.5 feet tall. It is known for its distinctive odor, which usually repels animals that may be poisoned by it otherwise.
Stinkgrass can grow in a variety of soil types from moist to dry. They grow rapidly into adults after germination. Seedlings of stinkgrass are difficult to distinguish from other grasses.
Leaf blades can be either flat or folded and are light-green colored. The undersides of the leaves are smooth and glossy, while the top is rough and hairy on the margins. At the leaf collar is a dense fringe of straight hairs. Stems usually branch at the base.
Stinkgrass plant
Stinkgrass plant at leaf node. Photo courtesy of Harry Rose. Licensed under CC BY 2.0.
Stinkgrass blooms from mid-summer to early autumn, lasting up to 2 weeks per plant. The seedhead grows in a triangular shape with a grayish-green color, which helps distinguish stinkgrass from other grasses. Seeds grow in spikelets that are loosley arranged in the seedhead. Upon maturity, seedheads become more brownish in color.
Stinkgrass seedhead
Stinkgrass seedhead. Photo courtesy of Forest and Kim Starr. Licensed under CC BY 2.0.
Stinkgrass can compete with various crops for nutrients and moisture. It is also toxic to animals.
Stinkgrass will not survive if mowed repeatedly. In the presence of more competetive crops, the weed will not prosper well either.
Most preemergence and postemergence herbicides will effectively control stinkgrass. Imazethapyr will not provide control for stinkgrass. Please contact your local weed specialist to learn what is most effective in your area and how to use it best. Always read and follow all label instructions.