A Styrax tree left alone produces almost no resin. Benzoin is a wound response: the tree seals cuts in its bark with a balsamic sap that hardens in air. Harvesting means making those cuts, waiting, and collecting what the tree has made.
The two systems
Laos (Siam benzoin). Styrax tonkinensis comes up naturally when upland rice fields are left fallow. Farmers protect the seedlings, and after six to eight years the trees are large enough to tap. They are worked for roughly a decade, then the land goes back into cultivation. Benzoin here is one product in a rotation, not a plantation crop.
Sumatra (Sumatra benzoin). Styrax benzoin is planted deliberately in kemenyan gardens in the Batak highlands, often mixed with other trees. Gardens are inherited and tapped for decades. There is a richer local vocabulary of grades, tools and rituals around the harvest, reflecting how long it has been an economy.
The cycle
- Tapping. In the dry season the farmer climbs the tree, or works from the ground on younger trees, and makes shallow, angled cuts or small triangular notches in the bark, often in vertical rows. The cuts go through the bark but not deep into the wood. Too few and the yield is poor; too many and the tree declines.
- Exudation. A milky sap oozes from each wound and gradually hardens. In the first weeks it is soft and white; as it oxidizes and loses volatiles it turns yellow, then amber, and becomes brittle.
- Collection. After two to three months the farmer returns and scrapes the hardened resin off the bark with a knife or spatula. The cleanest pieces are the tears that formed and stayed on the tree. Resin that dripped down the trunk or fell to the ground is collected separately.
- Sorting. At home the harvest is sorted by size, colour and cleanliness. Large pale tears go into the top grade; broken pieces, bark-contaminated resin and dust go into successively lower grades.
- Sale. Farmers sell to village collectors who consolidate lots and sell on to exporters in Luang Prabang or Medan. Most of the price is added after the farm gate.
Yield and economics
A mature tree yields somewhere between a few hundred grams and one to two kilograms of resin a year, higher in Sumatra where trees are older and larger. A family garden of a few hundred trees can produce a few hundred kilograms in a good season. Farm-gate prices are low compared with the retail price of sorted tears in Europe, and this gap, more than any ecological limit, is what threatens supply: when prices fall, young people leave the gardens and trees are not replanted.
What determines quality
- Age and vigour of the tree. Older, healthy trees give larger, cleaner tears.
- Season. Dry-season tapping gives resin that hardens cleanly; wet-season tapping gives softer, dirtier resin.
- Collection discipline. Tears scraped carefully off the bark are worth several times the price of scrapings mixed with bark and soil.
- Handling. Resin stored in the open or in heat softens, agglomerates and loses aroma. See How to store resins.
What the buyer sees
By the time benzoin reaches a shop it has been sorted at least twice and often re-sorted by the exporter. Whole pale tears mean a farmer who took care and a buyer who paid for it. Dark, dusty, bark-flecked lumps mean the bottom of somebody’s bag. Both are real benzoin; only one is worth paying Siam prices for. See How to buy benzoin.
Frequently asked questions
How long does it take to harvest benzoin?
From tapping to collection takes about two to three months. A tree is tapped once a year, usually in the dry season, and yields between a few hundred grams and a couple of kilograms of resin depending on age, origin and grade.
Does tapping kill the tree?
Not if done carefully. Styrax trees are tapped for ten to twenty years or more. Over-tapping shortens their life, and in Laos the trees are often part of a rice-fallow rotation and are eventually cut anyway.
Is benzoin harvesting sustainable?
Broadly yes: it is a low-input agroforestry crop that keeps trees on hillsides that would otherwise be cleared. The pressures are economic, not ecological: low farm-gate prices push farmers toward other crops.
Sources & further reading
- benzoin
- harvest
- tapping
- laos
- sumatra
