Gramineae

Aristida capensis Thunb. var. barbata; Aristida capensis Thunb. var. genuina Henr.; Aristida capensis Thunb. var. macropus (Nees) Trin. & Rupr.; Aristida capensis Thunb. non Stipagrostis capensis Nees: Aristida capensis Thunb. var. dieterleniana Schweick; Aristida sericans Hack. apud Schinz; Aristida capensis Thunb. var. canescens Trin. & Rupr..

Bushman grass, Cape bushman grass.

Arundinoideae; Aristideae.

The genus Stipagrostis contains species that occur in xerophytic open habitats that include desert and semi-desert and also dunes. There are 50 species occurring in Africa, southwest Asia and northwest India, of which 27 are indigenous to southern Africa, 24 of which are endemic. This indicates that the arid regions of southern Africa, especially the south-west, are an important centre of diversity for this genus. Stipagrostis zeyheri has four subspecies that occur along the west, south and east coast of South Africa and in the eastern interior in sandy habitats, including coastal dunes. Subspecies macropus is found along the west coast of South Africa, subspecies zeyheri in the fynbos of the western Cape, subspecies barbata along the southern and eastern coast and subspecies sericans in the eastern interior and Highveld.

A robust perennial grass that may be densely tufted or shortly rhizomatous and grows to a height of 700-900 mm tall. The leaf blades are setaceous (bristle-like) and are 200-500 mm long, depending on the subspecies, and may be folded or rolled. The culms are narrow (1.2-5.0 mm wide) and the leaf blades are flaccid or erect and rigid (in subspecies zeyheri) and mainly basal. The ligule is a fringe of hairs. Inflorescence consists of an open or contracted panicle. The spikelets are solitary and 15-19 mm long, excluding the awns. The spikelets disarticulate above the glumes. Rachilla terminated by a female fertile floret. There are two unequal glumes that are long relative to the adjacent lemmas. The glumes are awnless and the lower glume is 3-nerved. The lemma is awned with three awns that have a basal column and are much longer than the body of the lemma. All three awns are plumose to the branching point and excurrent into a naked apex. The callus of the awn is 1.0-2.5 mm long with a distinct, naked, pungent tip.
There are four subspecies of Stipagrostis zeyheri, namely barbata, macropus, sericans and zeyheri. In subspecies barbata the leaves are flaccid, often curling and almost overtop the inflorescence, whereas, at least in subspecies zeyheri, the leaves are erect and rigid. Subspecies sericans has long-hairy glumes and sometimes lacks lemma articulation, whereas the other three subspecies articulate near the apex of the lemma and the glumes are glabrous, scabrid or hairy with very short hairs. Subspecies macropus has plumose awns with long dirt-white or yellow hairs, whereas the other subspecies have glabrous awns. Subspecies zeyheri and macropus are shortly rhizomatous whereas the other two subspecies have tufted culms.

A natural sand stabiliser on coastal dunes and in sandy areas in the interior. A moderate to poor grazing grass with poor leaf production and hard leaves so that it is only grazed when no other more palatable grasses are available.

Chromosome base number, x = 11.

C₄ photosynthetic pathway.

Not toxic

Grows in temperate regions with 300-800 mm of annual rainfall. It is often found in disturbed areas such as previously cultivated lands, but is almost entirely restricted to sandy soils. Subspecies barbata grows in coastal dunes, where it forms dense stands in areas protected from the wind, such as on the margins of coastal dune thicket. It stabilises mobile sand in these areas, but does not tolerate highly mobile dunes or saline conditions, as would be found in the pioneer dune zone close to the sea.

Grows in coastal dunes (subspecies barbata), sandy soils or old cultivated lands.

Not cultivated or artificially propagated.

Grows and flowers at various times of the year depending on the season of rainfall. Mostly growth and flowering coincides with the season of maximum rainfall, but subspecies zeyheri flowers in summer although it is found in an area with winter maximum rainfall.

None known.

Slow-growing.

Gibbs-Russell, G.E., Watson, L., Koekemoer, M., Smook, L. Barker, N.P., Anderson, H.M., Dallwitz, M.J. 1989. Grasses of southern Africa. Memoirs of the Botanical Survey of South Africa, No. 58, National Botanical Institute, Pretoria.