Stenotaphrum secundatum (Walt.) Kuntze
Buffalo grass (Australia), St Augustine grass (Florida, United States).
A hardy perennial, creeping extensively by means of branched rhizomes and many-noded stolons. Exceedingly variable in size, the culms rising above the ground for 6-40 cm or more, much branched from numerous nodes, the branches trailing, producing flowering stems or fin-shaped tufts of leaves. Leaf- sheaths strongly compressed and keeled; leaves nearly always glabrous except near the ligule, blades up to 12 mm wide, folded at first, then expanded, usually rounded or obtuse; ligule a fringe of short hairs. Inflorescence a false (or, rarely, a true) one- sided spike, 4-15 cm long, terminating the culm and each flowering branch; central axis thick, swollen, flat on one surface, deeply hollowed out on the other, each cavity containing a single spikelet or shoot spike of two to four spikelets borne alternately on either side of a wavy middle ridge. Spikelets 4.5-5 mm long, sessile, acute, awnless, glabrous, light green (Chippendall, 1955). St Augustine grass is more robust and taller than buffalo grass, which is used for lawns. S. secundatum var. variegatum is used as a decorative indoor plant.
Native to North America, West Indies, Australia. Now widely distributed as a lawn grass.
Spring, summer and autumn.
Sea-level to 800 m.
Grows in humid areas, along the coast.
Tolerant of short dry periods.
It will grow on a wide range of soils, and is particularly adapted to the muck soils of the Florida Everglades coastal sands and alkaline soils. In Puerto Rico, cv. Roselawn does best on soils rich in lime, and on steep sandy soils (Vicente-Chandler et al., 1953).
It spreads quickly by means of stolons. It does not produce seed.
Cuttings will establish in roughly prepared land, but good land preparation will usually pay.
Vegetative material is used for new plantings. Rooted runners are dug or disc-harrowed into the soil, 30-40 cm apart in rows 60-80 cm apart, and preferably rolled afterwards. A hectare of cuttings will plant about 10 ha of land.
Early in the wet season.
It is rather slow to cover the ground, but eventually provides a dense sward which crowds out weeds.
The creeping flat stems of St Augustine grass root to form dense sods which stand trampling and heavy grazing.
It should be grazed every second week down to 6 cm (Göhl, 1975), leaving sufficient leaf area for the plant to produce the carbohydrates it needs for growth without depleting its underground reserves (Vicente-Chandler et al., 1953). It takes time to recover if grazed too closely. The herbage matures and becomes unpalatable very rapidly. An annual application of 350-500 kg/ha of 0:8:24 fertilizer is usually applied.
It can be made into useful silage (Bennett, 1973).
It contains about 1 percent of oxalates in the dry matter, but is not toxic (García-Rivera & Morris, 1955).
'Roselawn' is used as a pasture forage (Bennett, 1973).
It is subject to brownpatch in the United States.
Its ability to form a dense sod, its suitability for lawns. Its ability to grow on the muck soils of Florida.
Its coarseness and general low productivity, its lack of seed production.
It survives frosts.
It thrives in shaded areas and so is well adapted for lawns.
Some damage is done by the cinch bug (Blissus leucopterus) in the United States.
Fairly palatable when young, but quickly loses palatability.
Göhl (1975) records only one analysis of hay. The hay contained 6.7 percent crude protein, 32.5 percent crude fibre, 3.7 percent ash, 2.7 percent ether extract and 54.4 percent nitrogen-free extract in the dry matter. The digestibility of the dry matter was 50.3 percent, of the crude protein 30.7 percent, and of the crude fibre 49.3 percent.
In moist swampy soil near the sea-shore in the United States and southern Africa.
It will stand a good deal of flooding in Florida.
It should be well fertilized, especially with nitrogen. In Florida, two applications of 125 kg/ha a year are recommended.
2n=18, 20, 36, 54, 72 (Fedorov, 1974).
Kidder (1952) recorded a live-weight gain of 2 250 kg/ha in one year on a St Augustine grass pasture on organic soil in Florida. This result was never repeated. The experiment was conducted in an area with extremely favourable moisture and temperature conditions, while the animals were supplemented daily with 450 g of cotton-seed meal. In a ten-year grazing experiment on St Augustine grass cv. Roselawn in Florida, the average daily gain was 6.35 kg/ha from April to June, and 0.8 kg/ha during winter (Haines et al., 1965). The pasture should carry seven yearlings per hectare all year, with surplus pasture made into silage (Bennett, 1973).
Haines et al., 1965.
It is a sea-shore grass and will withstand salt spray (Wheeler, 1950).