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Graminae
Common names
Common russet grass, besem grass (Africa).
Description
A densely tufted perennial with culms 20-90 cm high, simple,
lowest leaf-sheaths densely hairy at the base, splitting into fibres, leaves
otherwise hairy or glabrous. The blades exceedingly variable in length
and width, usually 15- 40 cm long and up to 7 mm wide. Panicle 40 cm long,
open and loose. Spikelets 10- 13 mm long, unequally and often long-pedicelled,
solitary or in pairs, light, dark or dull brown, glumes truncate, obtuse,
glabrous, callus of upper floret 0.5- 1.3 mm long, two-toothed, bearded
with white hairs, the lemma hairy (Chippendall, 1955).
Altitude range
300-2 750 m in Tanzania.
Rainfall requirements
It generally occurs in rainfalls varying from 750-1 000 mm.
Drought tolerance
It is not very tolerant of drought.
Soil requirements
In Tanzania it vegetates an infertile red earth (latosolic
soil) derived from granitic rock and low in organic matter, lime, phosphorus
and potash. In Zambia it is common on poor, sandy soils. (Verboom &
Brunt, 1970). In Ghana it is common on rocky hillsides and shallow soils
overlying impermeable ironstone hardpan or bedrock. Soil texture varies
from sand to clay with a pH range from 5.0 to 6.0. It is also common on
riverine plains, on a range of soils with a pH from 5.2 to 7.5, with mottled
subsoils.
Vigour of growth and growth
rhythm
The grasses vegetate and come into flower during the rains,
but set seed and turn a reddish-yellow colour when their life cycle is
completed, even if the soil has not dried out. Loudetia flowers early.
After the rains, the whole herb mat dries off and usually burns. After
the fires there is a rather sparse growth of green leaves from the fire-scorched
perennial cushions and a little dry-season flowering by several grass species.
The main regrowth from the perennial cushions, however, does not occur
until after the rains have commenced (Vesey-Fitzgerald, 1963).
Response to fire
In Njombe, Tanzania, burning this pure vegetation every other
year in October gave the best grass production. Burning annually in June,
soon after the end of the rains, caused a vigorous growth of herbaceous
plants. With neither burning nor grazing, the grass lost its vigour (van
Rensburg, 1952).
Palatability
It has low palatability (Verboom & Brunt, 1970).
Chemical analysis and
digestibility
Dougall and Bogdan (1958) recorded 10.4 percent crude protein,
38.0 percent crude fibre, 5.6 percent ash, 1.8 percent ether extract and
44.2 percent nitrogen-free extract in the dry matter of fresh material
in early bloom in Kenya.
Natural habitat
Common on open grassland and in poorly drained, high-rainfall
sandy soils, but does not extend into the woodland.
Tolerance to flooding
It is common on seasonally flooded valley grasslands or dambos
in Central Africa (Vesey-Fitzgerald, 1963).
Genetics and reproduction
2n=24, 40, 60 (Fedorov, 1974).
Economics
Where the species is dominant, it is possibly an indication
of veld mismanagement (Chippendall & Crook, 1976).
Further reading
Lamotte, 1979; Vesey-Fitzgerald, 1963.
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