Scientific Name
Taeniatherum caput-medusae (L.) Nevski (Synonyms: Elymus caput-medusae; Taeniatherum asperum)
Common Name(s)
Medusahead
Tribe / Family Name
Triticeae
Flowering Period
May to June
Symbol
TACA8
Description
Medusahead is an introduced cool-season winter annual bunchgrass that reproduces by seeds. Culms usually range from 10–55 cm in height. Its inflorescence is a dense, erect to occasionally nodding spike 2–6 cm long and not disarticulating at maturity. Spikelets are 2 per rachis node, 2(3)-flowered: the lowest florets perfect; the upper florets reduced, sterile (occasionally obsolete); spikelets awned: the lemma awns extend into flattened and divergent awns usually 30–70 mm long. Auricles are small (up to 0.5 mm long) and finger-like. Ligules are very short (up to 0.6 mm long), membranous, obtuse to truncate, and erose.
General Info
This effective colonizer can be found in post-fire settings, as well as open ground, disturbed areas, overgrazed rangelands, waste places, dry roadsides and abused sagebrush slopes, foothills, and plains.
Similar Species
Medusahead looks somewhat similar to bottlebrush squirreltail (Elymus elymoides) and foxtail barley (Hordeum jubatum). Medusahead is an introduced winter annual grass with seed heads that do not disarticulate at maturity, while both squirretail and foxtail barley are native perennial grasses with seed heads that disarticulate at maturity.
Picture of growth habit.
Close-up picture of spike inflorescence.
Close-up picture of spikelet.
Illustration of medusahead. USDA-NRCS PLANTS Database / Hitchcock, A.S. (rev. A. Chase). 1950. <i>Manual of the grasses of the United States</i>. USDA Miscellaneous Publication No. 200. Washington, DC.