Diarrhena americana, also known as American beak grass or American beakgrain, is a native, perennial bunchgrass of North America.[2][3]

Historically, Diarrhena americana was the only species of beak grass recognized in the United States; however studies have suggested that the known beak grass is to be classified into two distinct species, Diarrhena americana and Diarrhena obovata.[4]

Distribution

Diarrhena americana naturally occurs throughout the Midwestern United States, including in eastern Oklahoma and Missouri; south to Alabama; east to Kentucky, the Appalachian Mountains and northern Maryland; and north to southern Illinois, Indiana, Ohio, and southern Michigan.[2][5][6]

The grass plant lives in rich cove forests and woodlands, preferring to grow in the moist soils of shaded ledges and riverbanks.[7] It grows in rich, moist woodlands from Missouri to Maryland and south to Oklahoma and Alabama.[2]

Description

In cultivation at the Berlin Botanical Garden

Diarrhena americana is a bunchgrass that grows in 2–3 feet (0.61–0.91 m) tall clumps. It has bright green leaf blades, that can grow up to 0.75 inches (1.9 cm) in width.[2]

These perennial plants can grow flowers that grow above the foliage, with 3 inch tall floral spikes, during the early to mid-summer. The culms range from 60–131 cm (24–52 in) high.[2][8][8]

By late summer the flowers turn into hard, brown seed heads.[2] Each seed is reduced to a blunt beak, which is where the common name of beak grass comes from, and this beak is dispersed.[8]

Cultivation

Diarrhena americana is cultivated as an ornamental grass, grown in traditional and wildlife gardens, and in natural landscaping projects.[8]

It is considered an easy plant to grow and maintain, not needing much sun or water while generally being a tough plant. It will tolerate drought, heavy shade, competition from eastern black walnuts, and urban air pollution.[8] When available, the plant will grow into dense clumps in moist rich soils in full shade.[8]

Conservation

Diarrhena americana is a listed endangered species in Maryland and Wisconsin, and a threatened species in Michigan.[3]

References

  1. ^ Hitchcock, A.S. (rev. A. Chase). 1950. Manual of the grasses of the United States. USDA Miscellaneous Publication No. 200. Washington, DC.
  2. ^ a b c d e f "Utah State University: Intermountain Herbarium". Archived from the original on June 11, 2011. Retrieved June 5, 2010.
  3. ^ a b "Diarrhena americana 'Beauv.'" (PDF). Retrieved May 30, 2009.
  4. ^ Brandenburg, D.M.; J.R. Estes; S.L. Collins (1991). "A Revision of Diarrhena (Poaceae) in the United States" (PDF). Torrey Bot. Club. Retrieved January 28, 2019.
  5. ^ "The Grass Manual on the Web.edu: Distribution map for Diarrhena americana". Archived from the original on April 28, 2014. Retrieved May 18, 2017.
  6. ^ "Beak Grass Diarrhena obovata". Retrieved January 28, 2019.
  7. ^ "Diarrhena americana Beauv". Retrieved January 28, 2019.
  8. ^ a b c d e f "Diarrhena americana". Retrieved 2014-04-25.
  • Koyama, T. and S. Kawano. 1964. Critical taxa of grasses with North American and eastern Asiatic distribution. Can. J. Bot. 42:859–864.
  • Tateoka, T. 1960. Cytology in grass systematics: A critical review. Nucleus (Calcutta) 3:81–110.