Red Brome Grass
Bromus rubens
(Bromus madritensis rubens)
Photographed at Mesquite Wash, Maricopa Co., Arizona. March 29, 2008.
ANNUAL: Annual weedy grass of spring growing in abundance after winters
with moderate to high rainfall amounts. Typically less than
½ meter tall.
FLOWERS: The red awns makes this one of the more attractive annual
grasses. Densely packed upright spikelets.
ARMED. Mature spikelets have barbed awns which cause them to readily
penetrate socks, animal fur and sometimes the skin.
LEAVES: Blades are narrow, a few mm wide.
RANGE: This non-native, invasive weed is now frequent to abundant almost
throughout the Sonoran Desert in Arizona and Mexico.
FRUIT: Spikelets containing several mature grain seeds disarticulate
from the plant and are dispersed bur-fashion.
This invasive weed not only competes with native herbs and grasses, it also promotes range fires in the Sonoran Desert where most plants are not fire-adapted. The disruption to the natural ecosystem cannot be understated. Originally introduced as a range grass, now even ranchers find it a nuisance because the barbed spikelets cause injury to the gums of cattle.