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Graminae
Common names
Tambookie grass (Australia), fine thatching grass (South Africa),
fine hood grass (Kenya).
Description
Slender perennial up to 150 cm high. Panicle narrow, loose,
often over 30 cm long with greenish or purplish racemes up to 15 mm long.
Panicle branches subtended by spathes, raceme pairs by spatheoles. At maturity
the raceme forms a distinctive L-shaped unit. In var. filipendula the two
racemes form an L- shaped unit, hence the common name "three o'clock thatching
grass". The lower raceme is nearly sessile; the upper has a filiform base.
Each raceme has a twisted awn that is hairy. The spikelets are glabrous.
Var. pilosa has hairy spikelets and usually three to four twisted hairy
awns to each pair of racemes (Chippendall & Crook, 1976).
Distribution
Africa, Sri Lanka, Burma, Australia.
Altitude range
Sea-level to 2 250 m. In Zaire it succeeds H. diplandra at
elevations below 1 700 m when H. diplandra formation is subjected to repeated
crop growing (Risopoulos, 1966).
Rainfall requirements
It requires a rainfall in excess of 625 mm.
Response to defoliation
At Mt Makulu Research Station, Zambia, cutting H. filipendula
pastures twice or four times a year (according to the frequency with which
it reached a height of 30 cm) over a period of nine years changed the botanical
composition. The dominance of shorter grasses, such as Cynodon dactylon,
Digitaria setivalva, Heteropogon contortus and Microchloa caffra, offered
an improvement in nutritive value (van Rensburg, 1968). In Uganda heavy
stocking led to its replacement by Brachiaria decumbens, which is a much
more nutritious grass (Harrington & Pratchett, 1974b).
Grazing management
It generally requires periodic burning late in the dry season.
Biennial fires encouraged H. filipendula (Harrington & Pratchett, 1974b)
and Themeda triandra in Uganda.
Response to fire
Burning late in the dry season in Zambia controls encroachment
of Acacia spp., but if done too often it leads to decreased plant cover
after three years ground cover by H. filipendula was halved (Brockington,
1961).
Dry-matter and green-matter
yields
Keya (1973) obtained 3 671 kg DM/ha over 14 months from unfertilized
grass with linear increases up to 9 883 kg with 300 kg N/ha plus 105 kg
P/ha from a Hyparrhenia grassland of H. filipendula, H. cymbaria and Hyperthelia
dissoluta in Africa. In Zaire it produced 28 798 kg/ha and 25 627 kg/ha
of green matter in 1958 and 1959, respectively (Risopoulos, 1966).
Toxicity
Ndyanabo (1974) recorded 0.46 percent total oxalic acid in
the dry matter, but no toxicity.
Palatability
Valuable grazing early in the rainy season. Less woody than
other Hyparrhenia spp., but palatability falls toward maturity.
Chemical analysis and
digestibility
Dougall and Bogdan (1958) recorded 6.6 percent crude protein,
36.3 percent crude fibre, 5.7 percent ash, 1.8 percent ether extract and
49.5 percent nitrogen-free extract in the dry matter at the fresh early
bloom stage in Kenya. It is not regarded as a desirable grazing grass in
Uganda (Harrington & Pratchett, 1972).
Natural habitat
Well-drained grassland and open woodland. Common in the African
miombo.
Fertilizer requirements
Hyparrhenia spp. grassland yield of dry matter increased from
3 671 kg/ha unfertilized to 7 594 kg/ha fertilized with 300 kg N/ha and
in association with 105 kg/ha of P2O5 from 4 477 kg/ha to 9 883 kg/ ha.
It was concluded, however, that it was uneconomical to fertilize pure natural
grassland and that legumes, e.g. Desmodium spp., should be introduced to
make better use of fertilizer (Keya, 1973).
Genetics and reproduction
2n=40 (Fedorov, 1974).
Economics
It is commonly used for thatching.
Animal production
No specific quantitative figures have been found (see H. hirta).
Further reading
Risopoulos, 1966.
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