Leucaena management in West Timor and Cape York

• Balai Pengkajian Teknologi Pertanian, Indonesia
• University of Nusa Cendana, Indonesia
• Central Research Institute for Animal Sciences, Indonesia
• Comalco Ltd, Australia

In Nusa Tenggara Timor (NTT), Indonesia, cattle husbandry provides 30-80% of farmers' cash income, although cattle productivity in the region is still considered to be low. Finding sufficient quality feed is a major constraint, especially in the dry season. Over the past 50 years cattle productivity in the Amarasi district near Kupang has exceeded the provincial average, primarily due to the ready supply of the high quality fodder Leucaena leucocephala (leucaena). In the 1980s leucaena covered two thirds of the district, but the devastating effects of the leucaena psyllid insect (Heteropsylla cubana) and the subsequent over-exploitation of forage resources threatened the sustainability of the Amarasi system.
The mining company Comalco conducted a major regeneration program on Cape York, Queensland from the commencement of mining in 1966. Several different potential end-uses for the regeneration areas were developed through the 1970s and 80s - including improved pastures, forestry, agroforestry and establishment of native flora, but there was still uncertainty concerning the most appropriate end-use. Through the 90s, the preferred end-use changed from cattle grazing to self-sustaining, maintenance-free vegetation comprising a variety of native flora. This change had its basis in the uncertainties surrounding the future for cattle in the Cape following loss of the Weipa fresh beef market (previously supplied by Sudley Station - leased and operated by Comalco), and the reduction in the live export trade during the Asian economic crisis.
At the commencement of the project Comalco was negotiating with the Traditional Owners concerning the future of Sudley Station. Cattle production is one of the few economic enterprises suitable for Traditional Owners in the Weipa region.

The project aimed to build on the results of earlier ACIAR project activities, notably New Leucaenas for Southeast Asian, Pacific and Australian Agriculture, to improve the livelihoods of smallholder farmers in West Timor and indigenous communities on Cape York.

In West Timor the project team introduced improved cultivars of multipurpose trees (MPTs), including the highly productive and psyllid-resistant leucaena KX2 F1 hybrid (L. leucocephala x L. pallida). The MPTs were established in carefully selected on-farm research/demonstration sites in target villages, using a participatory approach. Train-the-trainers courses, field days and other promotional activities were conducted. Project members established seed orchards in West Timor and Bali and introduced a robust system for the mass production of rooted cuttings of the KX2 hybrid.
A socio-economic survey of Amarasi farmers was undertaken to determine factors responsible for success of the system in this district. In conjunction with survey a biophysical assessment of the agro-ecosystems using GIS techniques was also conducted to identify other areas physically suitable for growing leucaena.
At Weipa on Cape York, in consultation with Comalco and the Traditional Owners, the project team identified management strategies for the sustainable use of the leucaena/grass areas as holding pastures for cattle. Factors affecting the spread of leucaena as a weed were also studied.
Reduced supply of forage during the dry season, a problem common to both West Timor and Weipa, led to a study of the water use efficiency of leucaena systems, undertaken at the University of Queensland and in West Timor. These studies will help farmers make best use of limited dry season water reserves.

Comparisons made between Amarasi and North Central Timor (Timor Tengah Utara-TTU) districts showed striking differences, highlighted by the year-round growth rates of cattle in the two districts. Growth rates ranged between 400 and 600 grams per day for tethered cattle without project intervention in Amarasi and between 100 and 300 g/day for tethered cattle in TTU. Additional interventions could bring the range in Amarasi to between 800 and 1200 g/day, clearly indicating the potential of multipurpose trees (MPTs) and of Bali cattle to grow quickly on a sustainable resource base. The significant finding was that the critical differences were not in the biology of feed or cattle, or the physical characteristics of soil, terrain or rainfall but in the human factors of management and cultural practices. Thus, scaling up of these highly effective technologies, to emulate the successes of Amarasi, will involved engaging a human model of extension or political change. While remaining a researchable issue, new skills will be required. A geographic information system (GIS) has been useful in this respect but is limited when dealing with human factors that may vary over short distances and short periods.

Several varieties of Leucaena were tested by the project. the most easily cultivated variety was Tarramba, while the most productive was hybrid KX2 (albeit with remaining challenges for its effective vegetative and seed propagation). Some of these challenges were investigated by the project and some very good results were reported in the propagation of KX2 from cuttings. Studies of water use efficiency in Timor and Queensland produced encouraging results-the pruning of Leucaena at the end of the rainy season extends available water and feed availability well into the dry season when feed supply is more critical.

Several species of MPT and strains of Leucaena grew well and fattened cattle in smallholder systems in West Timor. These MPTs have potential for many parts of Indonesia and will undergo further research and development with farmers, especially on variety Tarramba and the new hybrid KX2. Reviewers recommended that the Australia-Indonesia team prepare for the release and large-scale adoption of new Leucaena varieties.