Gramineae

Andropogon excavatus Hochst.

Common turpentine grass, lemon grass, buchu grass, eau de Cologne grass, ginger grass

Panicoideae; Andropogonodae, Andropogoneae, Andropogoninae. There are about 40 species of Cymbopogon in tropical and subtropical Africa, Asia and Australia. Closely related to the tropical C. caesius.

Occurs from southern Africa to the north-eastern parts of Africa.

A robust tussocky perennial grass that grows to a height of 2,000 mm tall. Leaf blades are 50-300 mm long and up to 14 mm wide. The leaf blades are rounded at the base. The lowest culm nodes are exposed. The ligule is an unfringed to a fringed membrane. Inflorescence is a decompound leafy panicle with complex of partial inflorescences and intervening foliar organs. The spikelet-bearing axes are short, spikelike racemes, each pair with a spatheole. The spikelets are in pairs in 'long-and-short' combinations that are pedicellate/sessile. The pedicellate spikelets are male only or sterile. The sessile female fertile spikelets are 3-7 mm long and have a deep narrow groove on the lower glume.

This species is mostly unpalatable due to the bitter turpentine taste that results in grazers only utilizing it when there is virtually nothing else available. Often used as a thatching grass. In Lesotho it is used to line grain baskets to keep rodents away. Contains an essential oil with 18 ingredients.

Chromosome base number, x = 5 or 10

C₄ photosynthetic pathway.

None reported and considered to be non-toxic, although the essential oils that it contains render it unpalatable.

Occurs in areas where annual rainfall exceeds 500 mm per annum, but may occur less frequently in areas with lower rainfall. May be found in disturbed or undisturbed vegetation. Often found on roadsides, pastures, cultivated fields, as well as grasslands, savanna and forests, at altitudes ranging from 30 to 1,500 metres.

Grows in most soil types, but especially sandy and gravely soil.

C. excavatus is not propagated.

Flowers anytime from early summer until the end of winter.

None known

Moderate to 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.

Van Wyk, E. & Van Oudtshoorn, F. 1999. Guide to grasses of southern Africa. Briza Publications, Arcadia, South Africa.