Tragus koelerioides Aschers

Gramineae

 
Author: D. B. Hoare
Synonyms
Common names

Creeping carrot-seed grass

  Taxonomy

Chloridoideae; Chloridae sensu lato.

  Origin and geographic distribution

Endemic to southern Africa and is more common in the arid parts of the country. A ruderal weed that increases with overgrazing.

  Description

A perennial, rhizomatous and stoloniferous grass that grows to a height of 120-950 mm tall. The leaf blades are 10 to 50 mm long and up to 3 mm wide. Ligule is a very narrow fringed membrane. Inflorescence is narrowly spike-like. The spikelets are 3.5-4.8 mm long and are clustered on peduncles that are much shorter than the spikelets. The glume hairs are curved, not hooked at the tip.
T. koelerioides is the only perennial of the four species found in South Africa, the others are all annuals. The distinguishing feature is the curved glume hairs.

  Use

T. koelerioides is a ruderal weed that increases with overgrazing. It is therefore an indicator of overgrazing as well as a ground cover in overgrazed, arid areas and helps to prevent loss of topsoil.

  Cytology

Chromosome base number, x = 10.

  Leaf blade anatomy

C4 photosynthetic pathway. Biochemical type XyMS+. PCR sheath outlines are even and PCR sheath extensions are present. PCR cell chloroplasts have well-developed grana and are centripetal.

  Toxicity

Not toxic.

  Ecology

T. koelerioides is found in arid climates at moderate altitudes and low annual rainfall. It occurs in open vegetation on a variety of soil types and increases with over-grazing. It occurs infrequently and seldom becomes dominant.

  Soil requirements

It grows in a variety of soil types.

  Propagation and planting

T. koelerioides is a native pasture species and is not deliberately propagated.

  Growth and development

A winter- to spring-growing species that flowers anytime from July to May.

  Diseases and pests

None known.

  Performance

It is a poor grazing species due to the low leaf production, but is grazed where it occurs.

  Links
  References

Gibbs-Russell, G.E., Watson, L., Koekemoer, M., Smook, L. Barker, N.P., Anderson, H.M., Dallwitz, M.J. 1991. Grasses of southern Africa. Memoirs of the Botanical Survey of South Africa, No. 58, National Botanical Institute, Pretoria.