Chapter 4
Agroforestry

4.6 Fruit, nut, and resin orchards

Suggest if:

• Additional income or diversification is needed

Not recommended if:

• Land and tree tenure is insecure

Imperata grasslands do not forgive mistakes if management in planting trees is half-hearted! However, with care grasslands can be transformed into valuable orchards.

It is most important to:

• Practice good site preparation, use quality planting material, fertilize, and weed.

• Prevent fire and maintain fuelbreaks.

• Plant annual crops to provide income until fruit trees mature.

4.6.1 Choice of crops and planting material

Many orchard species have been successfully established in Imperata grasslands; some are more hardy than others and are more likely to survive and be useful to small-scale farmers even if not given much care. The climate and soil preferences of these crops are shown in Appendix D. For trees that do well under shade, such as coffee and cacao, see also Section 4.8, multistory agroforestry.

Use large, healthy planting stock. When planted, trees should be already taller than the vegetation in the prepared field. Large, vigorous planting stock will be better able to compete with the grass as it grows back. Grafted, budded, and marcotted planting materials will bear fruit sooner.

4.6.2 Site preparation

Especially in Imperata grasslands, good site preparation and proper establishment of a small orchard will be a better investment than poor site preparation for a larger orchard. Fast growth is necessary to outcompete the Imperata and at least partially suppress it to reduce the fire hazard.

Consider intercropping an annual crop. Thorough site preparation will help eliminate Imperata and improve tree growth, and the intercrop will provide income. See Section 4.4.2 for site preparation for intercrops.

If no annual crop will be intercropped:

1. Prepare the field.

2. Lay out planting spots. Use spacing recommended for the crop tree species. Lay out lines along the contour.

3. Prepare planting spots. Plow strips at least 1 m wide. Plow at least twice, preferably during the dry season. Or, cultivate circles at least 1 m in diameter. Thorough cultivation and wider strips will result in much better initial tree growth.

4. Establish a leguminous cover crop (see Section 4.3). This is recommended to suppress Imperata regrowth following spraying or pressing. It is strongly recommended to protect soil from erosion following cultivation.

5. Prepare holes. Dig holes at least one week before planting. The sunlight will help decompose organic material in the hole and help kill harmful pests and diseases. Holes should be large enough to accommodate the roots of the seedling and any manure or compost to be used. Break up the subsoil at the bottom of the hole. In compacted soils, dig a larger hole. Make separate piles for topsoil and subsoil removed from the hole.

4.6.3 Planting trees

1. Plant at the start of the rainy season.

2. Apply basal fertilizer if possible. Follow recommendations for local soils, placing rock phosphate or 50-100 g of urea or complete fertilizer at the bottom of the hole. Cover the fertilizer with a small amount of topsoil before setting the seedling. If available, place one half to one kilogram of manure or compost in the hole. On acid soils, add some lime, dolomite, or gypsum.

3. Prune any twisted roots and place the young tree in the hole.

4. Place topsoil from the original hole (mixed with compost if available) around the seedling and press firmly. If more soil is needed to fill the hole, use the piled subsoil.

5. Mulch. Use pulled weeds, cut grass, and cover crop foliage as mulch around the trees. Mulch as much as possible without creating a fire hazard or providing a breeding ground for termites.

4.6.4 Orchard maintenance

If the plantation is not well maintained it will have

• persistent Imperata

• possible fire, and

• low or no production.

To reduce fire risk and get early production, maintain the orchard as follows.

Fertilize. Use recommendations for local soils and the crop.

Ring weed. Weed as often as necessary, about 2-4 times a year depending upon the length of the rainy season. Clear grass and weeds from a circle 1 m diameter for small trees, 2 m for large trees.

Minimize competition between the leguminous cover crop and crop trees. Slash vines within circles at the base of trees, 2-4 m in diameter. Do this at the beginning of the dry season, and every 3-4 months during the wet season.

Maintain the leguminous cover crop (see Section 4.3). If the vines die or are not well established, sow additional seeds at the edge of the cleared circle around the tree, and direct vines away from the tree.

Maintain Mulch around the base of the trees.

Tend according to recommendations for the tree crop, using proper pruning techniques, and protecting the trees from insects and diseases.

4.6.5 Danger phase

The period between the time when the trees cast too much shade for intercrops and when the trees close canopy are years of high fire danger. Weeding and fertilization as recommended will help the trees grow faster and shorten this period. Weeding, herbicides, pressing, cover crops, and fuelbreaks can be used in combination to reduce fuel hazard and avoid loss of the plantation.

Some tree crops, such as pruned citrus, will never form a closed canopy to permanently suppress Imperata. Besides intercropping of annual crops and leguminous cover crops, another strategy is to develop a multistory agroforest to use all the growing space below and above the tree crop (Section 4.8).