General: Johnsongrass (Sorghum halepense) is tall, upright bunchgrass with large, open seedheads. Stems 6-8 feet high. Leaves long and wide with a white stripe down the center. Reproduces by rhizomes and seeds. Spikelets 1-flowered, in groups of 3 in open panicles. Flowers from early summer to fall.

Johnsongrass is an uncommon component of vegetation in the Lower Sonoran (Creosote-Bursage Flats) and Upper Sonoran (Mojave Desert Scrub) life zones. Around Las Vegas, keep an eye out for this species around Lake Mead and the lower Las Vegas Wash. Land managers are actively working to eradicate Johnsongrass, so hopefully you won't see it anywhere. Johnsongrass is on the list of "Watch Weeds" for the Lower Las Vegas Wash.

This is an noxious weed. If hikers and other visitors to the native habitats around Las Vegas see this species, please report the observation to the Nevada Department of Agriculture using their online forms. If you have this species on your private property, please consider eradicating it.

Family: Grass (Poaceae).

Other Names: Holcus halepensis, Sorghum miliaceum, Johnson Grass.

Plant Form: Tall, perennial grass forming dense stands.

Height: To about 8 feet.

Stems: Stem tall, erect, round, hollow.

Leaves: Alternate, linear; blades long and to about 1-inch wide. White stripe down the center, and distinct collar.

Flowers: Blooms early summer through fall. Inflorescence a large, open panicle, plume-like, oblong.

Seeds: Grain, finely striate, reddish-brown.

Habitat: Disturbed areas, ditches, roadsides, fields.

Elevation: To about 2,500 feet.

Distribution: Throughout North America; native to the Mediterranean region.

Comments: Johnsongrass is defined as a noxious weed in the state of Nevada.

For More Information: DiTomaso, J.M., and E.A. Healy. 2007. Weeds of California and other Western States. University of California Agricultural and Natural Resources Publication 3488. 2 Vol. ISBN 978-1-879906-69-3.