Two people stand on a grassy hillside in the King Range Wilderness, overlooking the Pacific Ocean.
California Poppies Headwaters Forest Reserve Kayaker enjoying the California Coastal National Monument Headwaters Forest Reserve King Range National Conservation Area
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Arcata Field Office

Medusahead Grass (Taeniatherum caput-medusae) 

Grass Family (Poaceae)

   Medusahead Grass
Photo Courtesy of CDFA

Description: Aggressive winter annual 1/2 to 2 feet (15 to 61 centimeters) tall. Leaf blades generally 1/8 inch (.32 cm) wide or less, rolled. Inflorescence long-awned spike nearly as wide as long. Mature awns or beards twisted, 1 to 4 inches 2.5 to 10 cm) long, stiff, finely barbed. Sometimes confused with foxtail or squirreltail, however spike head does not break apart as seeds mature. Individual awn-florets fall away, leaving a bristly head of awn-like glumes that will persist over winter.

Habitat: Native to Eurasia. Extremely competitive crowding out many native and desirable plants, invading millions of acres of semi-arid rangeland. Appears more commonly on high shrink-swell clay soils. Infested rangelands have suffered up to 75% reductions in grazing capacity. Introduces fire into non-fire prone ecosystems. Control of small, isolated infestations is critical.

Distribution: Medusahead grass is found throughout the interior northern California region in disturbed areas.

Flowering Period: Year round as rains allow, predominantly winter/spring.