Hyperthelia dissoluta (PROTA)
Hyperthelia dissoluta (Nees ex Steud.) Clayton
- Protologue: Kew Bull. 20: 441 (1966).
- Family: Poaceae (Gramineae)
- Chromosome number: 2n = 40
- Hyparrhenia dissoluta (Nees ex Steud.) C.E.Hubb. (1936).
- Yellow thatching grass, yellow hard grass, coarse thatching grass, yellow tambookie grass (En).
Origin and geographic distribution
Hyperthelia dissoluta occurs throughout tropical Africa, South Africa and the western Indian Ocean islands, and is introduced and naturalized in tropical America.
Mature stems are widely used for thatching and for making mats after the spikelets have fallen. The mats are used in ceilings, as partition walls and as screens around buildings and compounds. Individual screens are tied serially to make a fence. Dagaari people of Ghana make characteristic square baskets using the younger stems. Cattle eat the grass when it is young. Spikelets are pungently bristled and may injure the muzzle of feeding animals and inhibit browsing, but cattle search for the foliage below the inflorescence. Camels in Niger do not graze it at all.
Production and international trade
Hyperthelia dissoluta is only locally used.
According to the South African Standard for coarse thatching grass the cut length of Hyperthelia dissoluta stems should not be less than 1.2 m, stems should have a minimum and maximum diameter at the butt end of 1.2 mm and 2.5 mm, respectively, be acceptably straight (cut above the first node), be free of loose material, be workable, not be cut in the growing season, be fully grown and matured, and be free of seed when cut. The stems have some value for producing paper.
The grass is palatable when young, but too coarse when mature. It is completely grazed in the early stage, but at later stages the stems are usually left ungrazed and only the leaves are eaten. In a survey in South Africa, farmers ranked Hyperthelia dissoluta among the less palatable grasses. In Limpopo (South Africa) chemical analysis of the grass indicated per 100 g dry matter (dry matter content 94%): organic matter 90 g, crude protein 2.2 g, neutral detergent fibre 72 g, acid detergent fibre 34 g, in-vitro dry matter digestibility 44% and organic matter digestibility 46%. Analyses of browse species in West Africa indicated for Hyperthelia dissoluta (sampled in December) per 100 g dry matter (dry matter content 37%): crude protein 4.3 g, crude fibre 35 g, digestible protein 50%, net energy 3.4 MJ/kg, ash 11.3 g, Ca 0.36 g, P 0.08 g.
Adulterations and substitutes
Several Hyparrhenia species provide very similar thatching material, while many other grasses and palms leaves are used for the same purpose.
Tufted, perennial grass; stems 100–350 cm tall, yellow. Leaves alternate; sheath without auricles; ligule membranous, 2–3(–5) mm long, glabrous; blade linear, up to 30 cm × 6 mm, blue-green. Inflorescence a false panicle, composed of paired racemes subtended by spatheoles, erect, rather stiff, with 4–6 erect, nearly parallel tiers; spatheole narrowly lanceolate, 5–8 cm long, dry membranous, glabrous or sometimes hirsute, yellowish green eventually becoming reddish; peduncle ½–¾ as long as spatheole; racemes paired, erect, 2–3 cm long, 2-awned per pair (occasionally more), the lower raceme of a pair bearing a basal pair of homogamous, sterile or male, pedicelled spikelets 8–15 mm long; rachis filiform, fragile at the nodes, ciliate on margins; raceme-base filiform, unequal, the longer one 2–3 mm long, glabrous, extended into a characteristic, linear to oblong, 4–11 mm long appendage. Spikelets in pairs, sessile spikelet fertile, pedicelled spikelet sterile or male; sessile spikelet linear, 4–14 mm long, falling entire, callus cuneate, 3–6 mm long, white hairy, pungent, glumes dissimilar, exceeding apex of floret, lower glume oblong, coriaceous, deeply grooved, yellow, without keel, apex 2-fid, upper glume oblong, coriaceous, without keel, apex emarginate, unawned, sometimes mucronate, lower floret reduced to hyaline lemma, upper lemma oblong, 5–6 mm long, hyaline, without keel, apex 2-fid, with awn 5–10 cm long, yellowish, stamens 3; pedicelled spikelet lanceolate, 9–14 mm long, pedicel filiform, 4 mm long, setose, tip oblique, callus cuneate, c. 0.5 mm long, acute, glumes coriaceous, one glume with up to 6 mm long awn, lemmas 2, enclosed by glumes. Fruit a narrowly elliptic caryopsis.
Other botanical information
Hyperthelia is classified in the Andropogoneae and comprises 6 species, all except Hyperthelia dissoluta restricted to the area where the Central African Republic, DR Congo and Sudan meet. Hyperthelia is closely related to Hyparrhenia from which it is distinguished by the deep median groove in its lower glume and by the long appendage from the tip of its raceme-base.
Hyperthelia dissoluta is often a dominant species in tall-grass savanna and is common in deciduous bushland, Combretum woodland and wooded grassland, in fixed dunes, along riverbanks and roads and in disturbed places, including mining areas contaminated with nickel and molybdenum. It requires an annual rainfall over 625 mm, and occurs from sea-level up to 1350(–3000) m altitude. Hyperthelia dissoluta is commonly found on poor sandy soils. It is tolerant of fire. In East Africa Hyperthelia dissoluta dominated grassland is chiefly composed of tall grasses usually associated with Brachystegia woodland or a more open Commiphora woodland with Acacia spp. Soils are generally poor, sandy and derived from granite. These types of grassland occur at 450–1500 m altitude with an annual rainfall of 750–1200 mm falling between November and May. Most grasses are palatable when young but, if not heavily grazed, soon become woody. Hyperthelia dissoluta is also common in open, often almost treeless savanna with scattered Acacia trees occurring on red and black soils and some flood-plain areas at 450–1200 m altitude with 650–900 mm rainfall.
Propagation and planting
Hyperthelia dissoluta spreads mainly by seed.
In Zambia late dry season burning over a 3 year period of Hyparrhenia grassland with Hyperthelia dissoluta reduced competition from shrubby vegetation and halved the population of Hyparrhenia filipendula (Hochst.) Stapf. However, Hyperthelia dissoluta withstood the fires and increased slightly in population.
Diseases and pests
From Hyperthelia dissoluta affected by smut several fungi have been collected, including: Sporisorium ischaemoides, Sporisorium leelingianum, Sporisorium transfissum, and Sporisorium vanderystii.
Stems for thatching should be harvested when the plants are fully matured.
In experiments in DR Congo it has produced up to 27 t/ha green matter.
Hyperthelia dissoluta is common and has a wide area of distribution. As it is also well adapted to grazing and burning, there are no indications that it is under threat of genetic erosion. On the other hand, it also does not seem to be so dominant under various grazing intensities that it threatens other species or becomes weedy and invasive. No systematic ex-situ collections of germplasm are known to exist.
Hyperthelia dissoluta is likely to remain a valuable and widely available source of natural thatching material. More research is needed to assess its value as a forage in managed grasslands.
- Bingham, M.H., 1990. An ethno-botanical survey of Senanga West. Senanga West Agricultural Development Area, Department of Agriculture, Republic of Zambia. 27 pp.
- Burkill, H.M., 1994. The useful plants of West Tropical Africa. 2nd Edition. Volume 2, Families E–I. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 636 pp.
- Clayton, W.D., 1966. Studies in the Gramineae XII. Parahyparrhenia, Hyperthelia and Exotheca. Kew Bulletin 20: 433–449.
- Clayton, W.D. & Renvoize, S.A., 1982. Gramineae (part 3). In: Polhill, R.M. (Editor). Flora of Tropical East Africa. A.A. Balkema, Rotterdam, Netherlands. pp. 451–898.
- Clayton, W.D., Vorontsova, M.S., Harman, K.T. & Williamson, H., 2002–. GrassBase - the online world grass flora. [Internet] Royal Botanic Gardens, Kew, United Kingdom.http://www.kew.org/ data/grasses-db/. April 2011.
- Cope, T.A., 2002. Gramineae, tribe Andropogoneae. In: Pope, G.V. & Martins, E.S. (Editors). Flora Zambesiaca. Volume 10, part 4. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 190 pp.
- Phillips, S., 1995. Poaceae (Gramineae). In: Hedberg, I. & Edwards, S. (Editors). Flora of Ethiopia and Eritrea. Volume 7. Poaceae (Gramineae). The National Herbarium, Addis Ababa University, Addis Ababa, Ethiopia and Department of Systematic Botany, Uppsala University, Uppsala, Sweden. 420 pp.
- Poilecot, P., 1999. Les Poaceae du Niger. Boissiera 56: 1–766.
- Skerman, P.J. & Riveros, F., 1990. Tropical grasses. FAO Plant Production and Protection Series No 23. Rome, Italy. 832 pp.
- Williamson, J., 1955. Useful plants of Nyasaland. The Government Printer, Zomba, Nyasaland. 168 pp.
- Bogdan, A.V., 1977. Tropical pasture and fodder plants (grasses and legumes). Longman, London, United Kingdom. 475 pp.
- Brockington, N.R., 1961. Studies of the growth of a Hyparrhenia-domnantant grassland in northern Rhodesia. II. Fertilizer responses III. The effect of fire. Grass and Forage Science 16(1): 54–64.
- Cech, P.G., Edwards, P.J. & Olde Venterink, H., 2010. Why is abundance of herbaceous legumes low in African savanna? A test with two model species. Biotropica 42(5): 580–589.
- Chippindall, L.K.A. & Crook, A.O., 1976. 240 Grasses of southern Africa. 3 volumes. Collins, Salisbury, Zimbabwe.
- Le Houérou, H.N. (Editor), 1980. Browse in Africa: the current state of knowledge. Papers presented at the International Symposium on Browse in Africa, Addis Ababa, April 8–12, 1980, and other submissions. International Livestock Centre for Africa, Addis Ababa, Ethiopia. 491 pp.
- Matlebyane, M.M., Ng’ambi, J.W.W. & Aregheore, E.M., 2009. Relationships between chemical composition and in vitro digestibility of some common forage species used for ruminant livestock production in three chief areas of Capricorn Region, Limpopo province, South Africa. Research Journal of Agriculture and Biological Sciences 5(2): 138–149.
- Matlebyane, M.M., Ng’ambi, J.W.W. & Aregheore, E.M., 2010. Indigenous knowledge (IK) ranking of available browse and grass species and some shrubs used in medicinal and ethno veterinary practices in ruminant livestock production in Limpopo province, South Africa. Livestock Research for Rural Development 22(3): 54.
- Morgenthal, T., Maboeta, M. & van Rensburg, L., 2004. Revegetation of heavy metal contaminated mine dumps using locally serpentine-adapted grass species. South African Journal of Botany 70(5): 784–789.
- Panichev, N., Mabasa, W., Ngobeni, P., Mandiwana, K. & Panicheva, S., 2008. The oxidation of Cr(3) to Cr(6) in the environment by atmospheric oxygen during the bush fires. Journal of Hazardous Materials 153(3): 937–941.
- Sarwatt, S. & Mollel, E., undated. Grassland and pasture crops. [Internet] Country Pasture/Forage Resource Profiles: United Republic of Tanzania. FAO, Rome, Italy. http://www.fao.org/ ag/AGP/AGPC/doc/Counprof/ tanz.htm. April 2011.
- South African National Standard, 2004. Specification for grass. [Internet] SANS 10407:2004. Thatched roof construction. Edition 1. South African Thatchers Association, Lyttelton, South Africa. http://www.sa-thatchers.co.za/ wp-content/uploads/2010/09/ SpecificationForGrass.pdf. April 2011.
- Tobler, M.W., Cochard, R. & Edwards, P.J., 2003. The impact of cattle ranching on large-scale vegetation patterns in a coastal savanna in Tanzania. Journal of Applied Ecology 40(3): 430–444.
- Vánky, K., 2003. The smut fungi (Ustilaginomycetes) of Hyparrhenia (Poaceae). Fungal Diversity 12: 179–205.
- Williamson, J., 1955. Useful plants of Nyasaland. The Government Printer, Zomba, Nyasaland. 168 pp.
Sources of illustration
- Akoègninou, A., van der Burg, W.J. & van der Maesen, L.J.G. (Editors), 2006. Flore analytique du Bénin. Backhuys Publishers, Leiden, Netherlands. 1034 pp.
- S. Kativu, Tropical Resource Ecology Programme (TREP), Department of Biological Sciences, University of Zimbabwe, P.O. Box MP 167, Mount Pleasant, Harare, Zimbabwe
Correct citation of this article
Kativu, S., 2011. Hyperthelia dissoluta (Nees ex Steud.) Clayton. [Internet] Record from PROTA4U. Brink, M. & Achigan-Dako, E.G. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. <http://www.prota4u.org/search.asp>.
Accessed 14 November 2020.
- See the Prota4U database.