Establishment and management of leucaena in Latin America

Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.Leucaena leucocephala (leucaena) is native to Mexico and Central America and is currently naturalized in the majority of Latin American countries. Over the last 2 decades, considerable research and promotion of leucaena have been carried out in Colombia, Mexico, Cuba, Brazil, Paraguay and Argentina. Research focused on the agronomic and management options for feeding beef, dairy or dual-purpose animals, with some studies on germplasm, weediness issues, toxicity, organic fertilizer application and environmental services.Over the past 10‒15 years, establishment and management of leucaena feeding systems in Latin America have varied according to country. For instance, intensive Silvopastoral Systems (iSPS) models are widely promoted and successfully adopted in Colombia, Mexico, Cuba, Venezuela and Northeast Brazil. In ISS, leucaena is planted at high density (>10,000 trees/ha), in combination with improved tropical grass and high-value timber species (200‒400 trees/ha), and intensively managed employing rotational grazing.In Paraguay and Argentina, leucaena is planted in single or double hedgerows with inter-row alleys of 6‒8 m, following the configuration used in Australia and mainly focused on beef production. In Mexico, leucaena is also cultivated with Tithonia diversifolia or lemon trees. Meanwhile, in other countries such as Cuba, leucaena has been established as protein banks using single/twin rows with inter-row spacing of 2‒4 m for feeding beef, dairy or dual-purpose animals. Overall, paddock sizes for protein banks and ISS range between 0.3 and 50 ha, while single and twin hedgerow systems are generally established over larger areas (20‒500 ha). Despite the significant benefits demonstrated by research on leucaena feeding systems over the past 2 decades, coupled with successful outcomes for farmers who have adopted these systems, total area sown remains low across Latin America. This review provides a comparison between Latin American and Australian leucaena pasture systems, and recommendations for future collaborative research between countries.