Oxytenanthera abyssynica - (A.Rich.) Munro

(A.Rich.) Munro

Savanah Bamboo

Amaranthaceae Edible: Sap, Seed, Shoots Potential hazards — see below

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Ousmane Diallo

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Ousmane Diallo

gbif· cc-by-nc

Ousmane Diallo

Description

Oxytenanthera abyssynica is an evergreen Bamboo growing to 12 m (39ft) by 4 m (13ft) at a fast rate. See above for USDA hardiness. It is hardy to UK zone 10. The flowers are pollinated by Wind. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers dry or moist soil and can tolerate drought.

Edible Uses

Drink. Young shoots - cooked. They can be boiled, steamed or smoked, and can also be dried or salted for later use. Used as a famine food. Seeds - cooked and used like rice. It is ground into a flour and is also used for brewing alcoholic beverages. The sap from the stems can be drunk. It can also be fermented into a wine. To collect sap to make wine, the tips of young shoots are cut off, and the stem is bruised twice a day during a week. The exudate from the bruises is collected and left to ferment for 2 days. The resulting wine (‘ulanzi’) contains 5 - 5.5% alcohol. Upon flowering, the flower-heads are frequently covered with honey-dew[332

Medicinal Uses

Antidiarrhoeal Dysentery Skin Tonic UrinaryA leaf-decoction is valued in the treatment of urinary problems, being prescribed for a lack of urine, as well as for too much urine, particularly in cases of diabetes. The decoction is also administered for generalised oedemas and albuminurea. The leaf and culm are reported to contain an (unnamed) alkaloid. The hairs on the culm sheaths are rubbed off and used as a wound-dressing. This is mixed with the rhizome pith, which has been cooked to a mash, and the whole thing is bandaged on the affected area. The rhizome is used in the treatment of dysentery. The seed is ground into a meal, together with other grain, and used as a tonic for small children.

Known Hazards

On ripening, the spiky seed heads may cause wounds which are unresponsive to treatment.

Distribution

Tropical Africa - Senegal to Eritrea and Ethiopia, south to Angola, Mozambique and northern S. Africa.

Where It Grows

AFRICA: Angola, Benin, Burkina, Burundi, Cameroon, Central African Repu, Chad, Congo, Equatorial Guinea, Eritrea, Ethiopia, Gambia, Ghana, Guinea, Guinea-Bissau, Gulf of Guinea Is., Ivory Coast, Kenya, Malawi, Mali, Mozambique, Niger, Nigeria, Northern Provinces, Senegal, Sierra Leone, Sudan, Tanzania, Togo, Uganda, Zambia, Zaïre, Zimbabwe.

Cultivation

It is absent from closed forest and extends little into semi-arid wooded grassland and thicket. Prevailing average annual temperatures are 20 - 27°c, with monthly average daily maxima of 30 - 36°c and daily minima of 7 - 17°c. Locally occasional frost may occur; if severe, this may scorch leaves. Succeeds on a range of soils so long as they are moisture retentive and also well-drained. Clumps take up to 6 years (from rhizome offsets) or 8 years (from seedlings) to reach the stem harvesting stage. A pure stand of Oxytenanthera abyssinica contains up to 750 clumps and 30,000 stems per ha. A newly germinated seed produces a single shoot in the first year, which may reach 1 metre in height from a small rhizome. By the third year, several shoots 1.8 - 3 metres long and 12mm in diameter can be produced from a rhizome that is 30cm long. The plant reaches full height and diameter within 4 - 8 years. Bamboos have an interesting method of growth. Each plant produces a number of new stems annually - these stems grow to their maximum height in their first year of growth, subsequent growth in the stem being limited to the production of new side branches and leaves. In the case of some mature tropical species the new stem could be as much as 30 metres tall, with daily increases in height of 30cm or more during their peak growth time. This makes them some of the fastest-growing species in the world. New stems break through the soil surface in the rainy season, growing very quickly for their first 3 - 4 weeks then slowing down and reaching their final height after 2 - 4 months. Canes mature in 3 years, and may survive for 8 years, but they are over-mature and unsuitable for harvesting from 6 years of age onwards. Clumps of plants grown for sap production are thinned from the second year onwards to prevent stem congestion, while pruning branches to around 2 metres favours access, and loosening peripheral soil promotes rhizome extension and unhindered shoot emergence. Bamboos in general are usually monocarpic, living for many years before flowering, then flowering and seeding profusely for a period of 1 - 3 years before usually dying. Clumps can live for 30 years, but this is less when mass flowering occurs and rhizomes die with the stems. Mass flowering can occur every 7 years in Uganda, 14 years in Zambia or 20 - 21 years in Malawi, whilst sporadic flowering of individual plants has been widely and frequently noted. Sometimes clumps die after mass flowering, but in other instances they have been known to survive by sending up new canes from the rhizome.

Propagation

Seed - it remains viable for 6 - 18 months if stored at ambient temperatures under dry and pest-proof conditions, and is said to germinate better if first stored for a few months. Seed can be sown in light shade in a nursery seedbed or in containers. Germination rates vary from 30 - 80%, with the seed sprouting within 11 days in warm moist conditions but up to 4 months in cool dry conditions. Plants are grown on in the nursery for 8 - 24 months, being planted out into their permanent positions in the early part of the rainy season when they have at least two shoots, the larger of which is 30cm or more long. Division of the rootstock is an easy method of propagation. Early in the rainy season, rhizome sections 12 - 30cm long bearing healthy buds, or the lowest 45cm of a stem, are excavated and transplanted without delay. Stem cuttings.

Other Uses

Biomass Charcoal Fencing Fodder Fuel Furniture Repellent Shelterbelt Soil stabilization Wood. Agroforestry Uses: The plant is grown as a component of shelterbelts and windbreaks. It is used as a complementary crop in plantations of Cordia africana, Eucalyptus microtheca and Khaya senegalensis. The plants extensive root system makes it suitable for used in erosion control programmes in land rehabilitation. Clumps for sap (‘wine’) production are typically established within areas cropped for maize, potatoes, pyrethrum or wheat. Other Uses: The leaves, rubbed(?) on house-walls, are said to keep away lice. The strong woody culms are the most valued part of the plant, used as building material for huts, for making furniture and fencing, for splitting to weave into baskets and panniers, for spears, bows and arrows, musical instruments, xylophones, and tambourines, etc. Walking-sticks are commonly made by cutting suitably-sized culms with a piece of the basal rhizome. The dried canes are used as a fuel and are also made into charcoal.