1. Purpose of Agroforestry Integration
Integrating other species into Aquilaria plantations helps:
- Enhance soil fertility via nitrogen fixation
- Regulate microclimate (shade, humidity, wind) to improve tree growth and resin formation
- Increase biodiversity and support beneficial insects
- Provide short- to medium-term income through intercrops while Aquilaria matures
2. Nitrogen-Fixing Species
Nitrogen-fixing trees improve soil nutrient content, boost tree growth, and support beneficial fungi.
| Species | Common Name | Notes |
|---|---|---|
| Sesbania grandiflora | Agati / Hummingbird tree | Fast-growing; prunable; improves soil nitrogen |
| Erythrina variegata | Indian Coral Tree | Moderate shade; flowers attract pollinators; fixes nitrogen |
| Gliricidia sepium | Gliricidia | Excellent green manure; supports intercropping; easy pruning |
| Leucaena leucocephala | Ipil-ipil | Fast-growing; ideal for hedgerows or alley cropping |
| Albizia lebbeck | Siris tree | Tall; moderate shade; enhances soil structure |
Planting Tips:
- Interplant in rows or alleys between Aquilaria trees.
- Regular pruning ensures adequate light for Aquilaria.
- Use leaf litter as mulch or compost to improve organic matter.
3. Shade Trees
Shade trees help maintain microclimate, reduce heat stress, and improve resin quality.
| Species | Benefits | Notes |
|---|---|---|
| Coconut (Cocos nucifera) | Partial shade + income | Plant along row edges; requires careful spacing |
| Banana (Musa spp.) | Quick shade + biomass | Temporary shade for young trees |
| Fruit trees (Mango, Jackfruit, Citrus) | Shade + fruit | Adds income and biodiversity |
Notes:
- Young Aquilaria seedlings need partial shade (30–50%).
- Avoid overly dense shade, which can reduce growth and resin formation.
4. Intercrops
Intercrops provide income, ground cover, and soil protection while Aquilaria matures.
| Intercrop | Purpose | Notes |
|---|---|---|
| Coffee (Coffea spp.) | Shade-tolerant cash crop | Plant under partial shade; compatible with 3–4 m spacing |
| Cacao (Theobroma cacao) | Shade-loving cash crop | Requires 30–50% shade; integrates with nitrogen-fixers |
| Turmeric / Ginger | Ground cover + income | Short rotation; planted along alleys or edges |
| Legumes (Mungbean, Peanut) | Nitrogen-fixing + soil cover | Rotated seasonally to improve soil fertility |
| Herbs / Medicinals (Lemongrass, Basil, Turmeric) | Income + soil cover | Minimal shade; plant along alleys or edges |
Notes:
- Ensure intercrops do not compete excessively for water or nutrients.
- Rotate annual intercrops to maintain soil health.
- Maintain access paths for resin induction and tree management.
5. Integration Design Concepts
- Alley Cropping: Nitrogen-fixers and intercrops in alleys between Aquilaria rows.
- Cluster Planting: Core Aquilaria blocks surrounded by nitrogen-fixing and shade trees for biodiversity and microclimate regulation.
- Buffer Zones & Windbreaks: Fast-growing species (Erythrina, Gliricidia, Mahogany) along plantation edges to protect trees and soil.
6. Key Takeaways
- Nitrogen-fixing trees: Improve soil fertility and microbial activity for resin induction.
- Shade trees: Protect seedlings, maintain humidity, and support high-quality resin production.
- Intercrops: Generate early income, cover soil, and enhance biodiversity.
- Design Principle: Combine row planting for operational efficiency with agroforestry elements for ecological and economic sustainability.