FACT 98-04, June 1998 (updates NFTA 86-06)
A quick guide to multipurpose trees from around the world
Gliricidia sepium is a versatile, fast-growing tree favored by farmers for living fences, fuel, fodder, green manure, shade, support for crops, and erosion control. Common names include madre de cacao, mata ratón, palo de hierro, cocoite (Central America), kakawati (Philippines), gamal (Indonesia), quick stick (Jamaica) and gliricidia. Gliricidia sepium is not synonymous with G. maculata, a closely related but much less useful species.
Gliricidia sepium (Jacquin) Steudel is a small to medium sized tree attaining heights of 2 to 15 meters. It may be either a single or multiple stem tree with trunk diameters reaching 30 cm. The bark is grayish-brown to whitish and may be deeply furrowed on old, large diameter trees. Leaves are pinnately compound, alternate in arrangement and 20 to 30 cm in length. Leaflets are generally opposite in arrangement, oblong in shape and pointed at the tip. On some specimens leaflets may be elliptical with rounded tips. There are 7 to 25 leaflets per leaf and size increases towards the tip. Leaflets are 40 to 80 mm long and 20 to 40 mm wide (Lavin 1996).
Flower development corresponds to the beginning of the dry season when trees have lost their leaves. In its native range flowering occurs November through March. In areas without a pronounced dry season, flowering may occur throughout the year but few pods form (Lavin 1996, Simons 1996). Flowers are pink to light pink in color, fading to white with brown spots or faint purple with age (Lavin 1996). The flowers are pollinated by the larger solitary bees Xylocopa fimbriata and Centris species in the tree’s native range. Other potential pollinators have trouble accessing the flower due to the rigidity of the keel pedals (Simons 1996). A lack of effective pollinators will greatly hinder pod and seed production. Pods can reach full size, 10 to 20 cm, within 3 weeks of fertilization. The green succulent pods turn woody and yellow with maturity, which requires 35 to 60 days. Pods contain 3 to 10 seeds and are explosively dehiscent (Lavin 1996, Simons 1996). Seed collection is recommended prior to pods opening.
Gliricidia sepium is native to the lowland dry forests from sea level to 1,200 m. It is uncommon above this elevation because of its sensitivity to cold. The temperature range is 20 to 30° C. It performs poorly below this range but will tolerate temperatures as high as 42° C (Glover 1989). Rainfall is generally from 900 to 1,500 mm/year, but may be as low as 600 mm or as high as 3,500 mm (Simons 1996). The dry season varies from 3 to 8 months, however Gliricidia sepium survives dry seasons of 9 months in Indonesia.
It grows well on many soil types; volcanic, sandy, stony, and heavy clays, including Vertisols. It is reported to tolerate some salinity and slightly alkaline soils. It will tolerate acid soils, but not severe acidity (pH less than 4.5) nor high aluminum saturation (greater than 60%). An aggressive pioneer, gliricidia readily colonizes infertile soils and reclaims Imperata grasslands (MacDicken et al 1997). Its name gamal means ‘Imperata killer’. It sprouts quickly after fire and thus may benefit from burning.
The true native range of G. sepium is restricted to the dry and sub-humid lowlands of the Pacific coast of Mexico and Central America, and adjoining dry inland valleys (Simons 1996). Native Americans domesticated the species into other parts of Central America. The Spanish introduced it into the Caribbean and the Philippines. Over the last century gliricidia has become common throughout the tropics.
Living fence. Gliricidia sepium may be the most common living fence species in the tropics. Fence posts are established from large stakes (see Propagation). They may be planted at 1 to 2 m spacing and joined with barbed-wire or bamboo. Alternatively, they maybe planted 10 to 20 cm apart as a stockade and their branches interwoven (Stewart 1996). Fuelwood, stakes, fodder and green manure are harvested from fences.
Fuelwood. Hard and durable, the wood has a specific gravity of 0.5 to 0.8. It makes a good fuel, burning with little smoke and no sparks, and has a calorific value of 4,900 kcal/kg. Natural stands, secondary forests and woodlots of gliricidia have been managed for commercial fuel production (Glover 1989, Stewart 1996). The wood is also used for poles, timber, furniture and agricultural implements.
Fodder. Responding well to frequent cutting, gliricidia produces abundant amounts of nutritious fodder containing 18 to 30% crude protein. Livestock respond well to the fodder. Some animals are reluctant to eat gliricidia, but training may overcome this problem. Once gliricidia is accepted, subsequent offspring readily consume it. Toxicity problems are reported with non-ruminants. Pruning trees before the dry season enables coppice growth to be retained for use as dry season feed. Fodder plantings vary from hedgerows with 10 to 50 cm in-row spacing and 1 to 4 meter between row spacing, to block plantings of 50 x 50 cm to 1 x 3 m. Production varies from 2 to 20 t/ha (Glover 1989, Stewart 1996, Allison and Simons 1996). Pod peels are eaten by livestock as a dry season fodder in Bali.
Farming Systems. When used as mulch or green manure, the nitrogen-rich foliage improves crop production through the addition of nutrients, weed control, conservation of moisture and reduction of soil temperature. Leaf biomass is usually produced from hedgerows or fences around or in the cropping area. Companion crops include paddy and upland rice, corn, cassava and coconuts. Hedgerows are used on sloping farmland for erosion control and passive terrace formation. Hedgerow management should minimize competition with crops. Hedgerow systems can be labor intensive, which may limit their adoption. Gliricidia is used as a shade for tea, coffee and cacao; and as a support for cassava, yams, vanilla, pepper, and passionfruit. These crops also benefit from the soil improvement characteristic of gliricidia. The presence of gliricidia in fields reduces incidence of some fungal and insect attacks (Glover 1989, Stewart 1996).
Other uses. Flowers are bee forage. Cooked leaves and flowers are used as a human food. Gliricidia is used to make medicines, rodenticides and insecticides. It is also used as a windbreak and ornamental. Cut boles are used to propagate orchids.
Propagation. This species is easy to propagate by cutting or seed. Large sized cuttings, 1 to 2.5 m in length and 6 cm in diameter, are made from branches 1.5 to 2.0 years old. Small cuttings are 30 to 50 cm long and made from branches 6 to 12 months old. Branches used for cuttings should be straight and healthy, and without side branches. The top of the cutting should be cut on a slant to prevent water collection and subsequent rot. The bark on the lower portion of the cutting should be scarred through to the cambium with a sharp knife to encourage rooting. One-third of small cuttings can be buried. For large cuttings 50 cm is sufficient. Trees established from cuttings will have a shallow root system and a short bole. They are susceptible to uprooting by heavy winds.
Seed is yellow to brown in color with 4,500 to 11,000/kg. Under optimum storage conditions—6 to 10% moisture content at 4° C—seed remains viable for over 10 years (Allison & Simons 1996). At 50% moisture content and 17° C seed can be stored for a year (Hensleigh and Holaway 1988). Seed is sown without pre-treatment directly into nursery containers. Standard nursery management practices are recommended. Seedlings are ready for transplanting after 2 to 3 months in the nursery at a height of 30 cm. Direct sowing is possible with 2 to 3 seeds per planting position at a depth of 1 to 2 cm. Site preparation is required to reduce competition. Direct sowing and transplanting operations should coincide with the rainy season. Seedlings are sensitive to competition. Regular weed control should be practiced until trees are established.
Seed production. There is strong international demand for gliricidia seed. Depending on location and provenance, seed price varies from $2 to $120/kg. Seed shortages, particularly for superior provenances, indicate that seed production may be a profitable agricultural activity. In Southeast Asia, the International Centre for Research in Agroforestry (ICRAF), Winrock and local collaborators are developing seed production guidelines for farmers.
Gliricidia is relatively free from insect and disease problems. Boa and Lenné (1996) provide a list of reported problems.
Gliricidia sepium fixes atmospheric nitrogen with Rhizobium soil bacteria. If gliricidia is being introduced to a new area or degraded site, seed or plants should be inoculated with the appropriate Rhizobium bacteria before planting. A list of Rhizobium suppliers is available from FACT Net.
Growth and yield varies greatly among provenances. The Oxford Forestry Institute (OFI) has conducted extensive trials with 28 provenances. Provenance Retalhuleu (Guatemala) is superior for leaf and wood production, and stem length. Provenance Belan Rivas (Nicaragua) is consistently good for leaf and wood production. Other provenances are appropriate for specific sites or uses (Dunsdon and Simons 1996).
Allison, G.E. and A.J. Simons. 1996. Propagation and Husbandry. p. 49-71. In: J.L. Stewart, G.E. Allison, and A.J. Simons. Gliricidia sepium: genetic resources for farmers. Tropical Forestry Papers 33. Oxford Forestry Institute, Oxford, UK. 125 p.
Boa, E.R. and J.M. Lenné. Diseases and Insect Pests. p. 73-76. In: J.L. Stewart, G.E. Allison, and A.J. Simons. See Allison and Simons 1996.
Dunsdon, A.J. and A.J. Simons. 1996. Provenance and Progeny Trials. p. 93-118. In: J.L. Stewart, G.E. Allison, and A.J. Simons. See Allison and Simons 1996.
Glover, N. (ed) 1989. Gliricidia production and use. Nitrogen Fixing Tree Association, Waimanalo, Hawaii, USA. 44 p.
Hensleigh, T.E. and B.K. Holoway. 1988. Agrofroestry species for the Philippines. US Peace Corps, Washington DC. 404 p.
Lavin, M. 1996. Taxonomy. p. 3-17. In: J.L. Stewart, G.E. Allison, and A.J. Simons. See Allison and Simons 1996.
MacDicken, K.G., K. Hairiah, A. Otsamo, B. Duguma, N.M. Majid. 1997. Shade-based control of Imperata cylindrica: tree fallows and cover crops. Agroforestry Systems 36:131-149.
Simons, A.J. 1996 Ecology and reproductive biology. p.19-31. In: J.L. Stewart, G.E. Allison, and A.J. Simons. See Allison and Simons 1996.
Stewart, J.L. 1996. Utilization. p. 33-48. In: J.L. Stewart, G.E. Allison, and A.J. Simons. See Allison and Simons 1996.
A publication of the Forest, Farm, and Community Tree Network (FACT Net)