Sustainable Agriculture and the Environment in the Humid Tropics

The following HTML text is provided to enhance online readability. Many aspects of typography translate only awkwardly to HTML. Please use the page image as the authoritative form to ensure accuracy.

Sustainable Agriculture and the Environment in the HUMID TROPICS

compatibility. Ways of improving these systems include using better trees and woody shrubs and creating an orderly arrangement of trees, crops, and livestock.

IMPROVED TREES AND WOODY SHRUBS

Several trees and woody shrubs are used in traditional and natural fallow systems. Some commonly used species include Acioa baterii, Afzelia bella, Alchornea cordifolia, Anthonotha macrophylla, and Gliricidia sepium (Okigbo and Lal, 1977). Some improved species have several advantages in an agroforestry system, including their ability to fix nitrogen, grow fast, tolerate soil acidity, and withstand regular coppicing. Commonly recommended tree species are listed in Table 2-1. However, validation for and adaptation to specific local systems are essential. More must be known about the agronomic and ecological bases of the mixtures to increase their attractiveness and usefulness to farmers.

Multipurpose trees can also be grown on cropland or pastureland.

TABLE 2-1 Commonly Recommended Species for Agroforestry Systems in the Humid Tropics

Species	Growth Characteristic(s)	Uses
Acioa baterii	Fast-growing shrub	Alley cropping, nitrogen fixation
Albizia falcata	Tree grows to 30 m	Erosion control, nitrogen fixation
Albizia lebbeck	Tree grows to 25 m	Erosion control, nitrogen fixation
Anthonotha macrophylla	Fast-growing shrub	Alley cropping, nitrogen fixation
Calliandra calothyrsus	Fast-growing shrub to 8 m, on acid soils	Alley cropping, nitrogen fixation
Cassia siamea	Shrub grows to 8 m, vigorous coppicing	Fuelwood, nitrogen fixation, lumber
Erythrina spp.	Tree grows to 20 m, often thorny, coppices well	Live fences, nitrogen fixation, fuelwood, fodder
Flemingia macrophylla	Shrub grows to 3 m	Alley cropping, nitrogen fixation
Gliricidia sepium	Fast-growing tree to 20 m, vigorous coppicing	Alley cropping, nitrogen fixation, forage, fodder, staking material,
Inga spp.	Nitrogen-fixing shrub, acid-tolerant	Alley cropping, nitrogen fixation
Leucaena leucocephala	Tree grows to 20 m, fast growing on nonacid soils, vigorous coppicing	Fodder, fuelwood, erosion control, nitrogen fixation, alley cropping, staking material
Pangomia pinneta	Small tree grows to 8 m	Erosion control, live hedges
Sesbania spp.	Fast-growing low tree	Erosion control, nitrogen fixation

Free Resources

Related Titles