Sustainable Yield Limits in Agarwood Cultivation & Harvesting Definition:
The sustainable yield limit is the maximum amount of agarwood (chips, oil, or resinous wood) that can be harvested from a plantation or natural stand without depleting the resource, harming tree populations, or violating ecological and legal standards.
1. Plantation Context (Farm-Grown Aquilaria)
- Harvest age: Trees are typically inoculated at 5–7 years old, with harvestable resin after 3–5 years post-inoculation.
- Per tree sustainable resin yield:
- Average 200–500 g of agarwood chips per tree (medium-grade).
- Exceptional cases may yield up to 1–2 kg (but not across all trees).
- Harvest cycle: One tree should only be inoculated and harvested once every 5–7 years to avoid mortality from over-inoculation.
- Sustainable practice: Retain 10–20% of trees unharvested for genetic diversity and long-term plantation resilience.
2. Natural Forest Context (Wild Aquilaria/Gyrinops)
- Strict quotas: Many countries (including the Philippines under DENR & CITES) enforce very limited or zero quotas for wild harvesting.
- Non-detrimental finding (NDF): Must demonstrate that removal does not harm population recovery.
- Sustainable approach:
- Only harvest naturally dead or fallen trees.
- For living trees, remove ≤30% of resinous wood while allowing tree survival (partial harvesting, not clear-felling).
- Enforce minimum size limits (e.g., only trees >20–25 cm DBH).
3. Extraction & Processing
- Essential oil yield: 1 kg of agarwood chips → ~2–3 ml of essential oil (depending on grade).
- Sustainability rule of thumb: Ensure plantation chip supply matches or exceeds oil demand to prevent pressure on wild stocks.
4. General Sustainable Yield Guidelines
✅ Harvest only mature, resin-rich trees (not immature).
✅ Use artificial induction methods (e.g., Fusarium inoculation) rather than waiting for rare natural infection.
✅ Set annual harvest limits per hectare (e.g., no more than 10–15% of trees harvested in a cycle).
✅ Replant at least 2–3 seedlings for every tree harvested.
✅ Maintain records for CITES & DENR verification to prove sustainability.
In short:
- Plantations: ~200–500 g agarwood/tree every 5–7 years is sustainable.
- Wild populations: Harvest only dead/fallen trees or partial resin, with strict quotas.
- Overall: Never harvest more than the plantation’s annual increment (growth + resin formation).