Elymus repens

Quack grass

Family: Poaceae · Type: perennial · Not Native

Quack grass is a naturalized perennial grass found in the California Floristic Province and Great Basin in disturbed areas and cultivated fields at elevations below 2,150 meters. Flowering from April to August, this aggressive weed produces pale green to whitish flower spikes with sharp-tipped spikelets 10 to 27 millimeters long. Growing with robust rhizomatous stems 50 to 100 centimeters tall, it spreads rapidly through underground root systems. Its leaf blades are 6 to 14 millimeters wide, with distinctive strongly ribbed veins and small ear-like auricles less than 1 millimeter long. The grass produces 4 to 7 florets per spikelet, with lemmas tapering to sharp points or short awns.

Habitat: Weed of disturbed areas, cultivated fields

Bloom period: Apr-Aug

Elevation: < 2150 m

Bioregions: CA-FP, GB

California counties: Humboldt, Plumas, Lassen, San Francisco, San Mateo, Orange, Tulare, Yolo, Riverside, Alpine, Butte, Calaveras, Del Norte, Kern, Napa, Nevada, San Diego, Santa Barbara, Sierra, Siskiyou, Modoc, Trinity, San Luis Obispo, Mono, Shasta, Amador, San Joaquin, Alameda, Marin, Placer, El Dorado

Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Jepson eFlora, Cal-IPC, and more.