1. Importance of Irrigation
- Ensures optimal growth and survival, especially during the first 2–3 years.
- Supports resin induction, as controlled water stress can improve resin quality.
- Maintains consistent soil moisture, reducing mortality and stress.
2. Low-Cost Irrigation Options
- a. Manual Watering
- Method: Using watering cans or buckets.
- Pros: No infrastructure needed; suitable for small nurseries.
- Cons: Labor-intensive; impractical for large plantations.
- Best Use: Seedlings and small experimental plots.
- b. Basin or Ring Irrigation
- Method: Create small basins around each tree to hold water.
- Pros: Water goes directly to roots; low cost.
- Cons: Labor-intensive; requires monitoring.
- Best Use: Young trees in small plantations.
- c. Furrow or Flood Irrigation
- Method: Water channels between rows.
- Pros: Simple and uses gravity; suitable for gentle slopes.
- Cons: Water wastage; uneven distribution; risk of waterlogging.
- Best Use: Medium-scale plantations with appropriate soil and slope.
3. Intermediate Irrigation Options
- a. Soaker Hoses / Perforated Pipes
- Method: Hoses with holes laid along rows; water seeps slowly.
- Pros: Reduces evaporation; more uniform distribution; less labor than manual watering.
- Cons: Moderate installation cost; can clog.
- Best Use: Medium-scale plantations with limited water availability.
- b. Sprinkler Irrigation
- Method: Overhead sprinklers simulate rainfall.
- Pros: Covers larger areas; increases humidity.
- Cons: Evaporation losses; requires water pressure.
- Best Use: Medium-sized, uniform terrain plantations.
4. Advanced Irrigation: Drip Systems
- a. Components
- Mainline, sub-main, lateral pipes, drippers/emitters.
- Filters, pressure regulators, optional timers, and sensors.
- Optional integration with fertigation (liquid fertilizers).
- b. Advantages
- High water efficiency; minimal evaporation loss.
- Precise water delivery to root zone.
- Can be automated for labor savings.
- Supports fertigation, boosting growth and resin formation.
- c. Design Considerations
- Dripper placement: 2–3 per tree for seedlings, 3–5 for mature trees.
- Flow rate: 2–4 L/h for seedlings; 4–8 L/h for mature trees.
- Incorporate filtration to prevent clogging.
- Can use solar-powered pumps in remote areas.
- d. Best Use
- Large plantations (>1 ha).
- Areas with irregular rainfall or prolonged dry seasons.
- High-value plantations focused on premium resin or oil production.
5. Comparison Table
| System | Cost | Labor | Water Efficiency | Best Use |
|---|---|---|---|---|
| Manual | Very low | High | Low | Nursery, small plots |
| Basin / Furrow | Low | Moderate | Low-moderate | Small to medium plots |
| Soaker Hose | Moderate | Moderate | Moderate | Medium plots |
| Sprinkler | Moderate-High | Low | Moderate | Medium plots, uniform terrain |
| Drip | High initial | Low (automated) | High | Large plantations, premium production |
6. Key Takeaways
- Young trees require frequent watering; mature trees tolerate short dry periods.
- Low-cost options are feasible for small-scale plantations or nurseries.
- Drip irrigation maximizes water efficiency and labor savings for large or high-value plantations.
- Combine irrigation with rainwater harvesting or storage for sustainable water management.