CWMA

PO Box 364

Paonia, CO 81428

 

970-361-8262

fax: 720-880-3051


Email:contact@cwma.org

 

 

Medusahead

Taeniatherum caput-medusae

 

Keys to Identification

  • An aggressive winter annual grass
  • The 4 inch inflorescence persists after the plant has matured

Family: Grass (Poaceae)

 

Other Names: medusahead rye

 

USDA Code: TACA8

 

Legal Status: Colorado Noxious List A

Not yet found in Colorado.

 

Photo: Sue Donaldson, UNCE

 

 

Identification

Lifecycle: Winter annual

 

Growth form: Grass. 6-24 in tall. Germinates in fall. Matures later than other annuals.

 

Inflorescence: Long-awned spike. Head persists after seed fall. Awns are twisted, stiff when mature. May-June.

 

Seeds/Fruit: Awned-floret.

 

Leaves: Slender, rolled, 1/8 in wide.

 

Stems: Slender, jointed.

 

Roots: Fibrous.

 

Seedling: Yellow-green.

 

 

Similar Species

Exotics: Seedlings similar to downy brome.

 

 

Impacts

Agricultural: Unpalatable to livestock when mature. Aggressive. Degrades rangelands. Builds up duff layer that ties up nutrients and may contribute to fire.

 

Ecological: Degrades natural lands.

 

 

Habitat and Distribution

General requirements: Semi-arid clay soils.

 

Distribution: Western US.

 

Historical: Native to Mediterranean region.

 

 

Biology/Ecology

Life cycle: Annual.

 

Mode of reproduction: Seed.

 

Dispersal: Animal, wind, water.

 

 

Integrated Management Summary

Burning will remove the thick duff layer.

 

Early grazing may provide some control.

 

Herbicide treatments are most effective.

 

 

References

Maurer, T., Russo M. J. (Revision), Godell A. (Revision); ELEMENT STEWARDSHIP ABSTRACT for Taeniatherum caput-medusae; http://tncweeds.ucdavis.edu/esadocs/documnts/taencap.pdf

 

The PLANTS Database, database (version 5.1.1) 2000; National Plant Data Center, NRCS, USDA. Baton Rouge, LA 70874-4490 USA. http://plants.usda.gov Reference for: Taeniatherum caput-medusae

 

Whitson, T.D.(ed.), L.C. Burrill, S.A. Dewey, D.W. Cudney, B.E. Nelson, R.D. Lee, R. Parker. 2001. Weeds of the West. Western Society of Weed Science, in cooperation with the Western United States Land Grant Universities Cooperative Extension Services, Newark CA. pg. 493.

 

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