Resin production has played an important part in the Góis region’s economy, particularly in providing rural work. Although resin collection still continues today, it was at its peak between 1920 and 1970. It is difficult to get any idea of the industry that existed before 1920, but we do know that the major increase in resin production came about through the creation of the Pinhal Interior Norte – an area of 2,617 km2 that includes the concelho of Góis. This forested area was planted systematically with maritime pine trees (Pinus pinaster) between 1900 and 1950.

Pine resin is a viscous semi-liquid that is excreted by pine trees to seal and protect any wound to the tree. It is yellowy-brown in colour, and will harden in contact with the air to form a brittle, sticky crust. Fossilised pine resin is known as amber, and is a semi-precious gem.

Pine resin is used principally for the production of turpentine and rosin. Turpentine (the name derives from the terebinth tree, from whose sap the spirit was originally distilled) is used for thinning and dissolving paint and varnish, in shoe-polish and sealing wax. Turpentine is also added to many cleaning products due to its antiseptic properties and its pine scent. Rosin is used in paper glue and soap manufacture, varnishes and paints, and is perhaps best known for its use on the bows of stringed instruments such as violins. Crude pine resin was used in the past in sailing vessels, as a packing material and for waterproofing. Pine resin also has medicinal properties: it is known to be anti-pathogenic (this is its main function for the pine tree) and has over the years been used for abrasions and wounds, as a treatment for lice, and mixed with animal fat as a chest rub, or inhaler for nasal and throat ailments. In the past it was administered  on sugar cubes, or in honey, as a treatment for intestinal parasites and a general cure-all. It is also a stimulant, a diuretic, an astringent and an anti-spasmodic. (However, it should be noted that its vapour can burn the skin and eyes, damage the lungs and the central nervous system when inhaled, and cause kidney failure when ingested.)

An average sized pine tree can produce 3-4kg of resin per year. The pine trees produce the best quality resin when they are growing, so the bulk of the resin collection falls between April and September. The resin-tapper removes an area of bark at the base of the tree, exposing the wood below. He places metal pieces into the tree to direct the resin flow into a terracotta or plastic bowl. The resin-tapper collects the resin from the bowl and also from the cut in the tree. After the partially-crystallised resin is removed, the area is coated with an acidic solution that encourages the further flow of resin. Each year a cut is made higher up the trunk of the tree. Once the cut is beyond the reach of the resin-tapper he will start another cut on the opposite side of the tree. Over time the bark will grow over the original cut. The resin is stored in old oil drums, that are collected by the resin company.

We know from our research that there were at least four resin distillation companies in the concelho of Góis. Today only one remains, at Chã de Alvares. The resin arrives in oil drums that have a hole cut into the side. The hole is opened and the resin is poured into a large sump. The next process is to heat the resin until liquid, and to filter any particles out of the material. Traditionally, the resin would be heated by an open fire, in a large sealed vessel with a condensing coil, very similar to a whisky still. The turpentine would then be condensed, leaving the liquid rosin in the bottom of the distillation vessel. The rosin produced by this method would have a reddish-brown appearance. Modern distillation techniques use steam, and produce a far superior rosin that is golden-yellow in colour. Once the turpentine and rosin have been separated, the liquid rosin is poured into metal trays to cool and harden. When the rosin is hard it is broken manually with a large wooden maul into small pieces, that are then bagged ready for distribution.

Today there are many old pine trees in the region that are still tapped for resin, or trees that show the scars of decades of resin collection. Throughout the region it is possible to still find the terracotta bowls that were once used to collect pine resin, although the woodland may no longer be pine. In some areas, resin collection used to be the main source of income, and often co-existed with bee-keeping and charcoal-making. It is a fact that forests with active resin production have a lower incidence of forest fires, probably because the immediate community has a very high interest in the preservation of its trees – the first recorded forest fire in the whole freguesia of Alvares only occurred in 1970. The resin collected in Portugal and other Mediterranean countries is considered to be top quality, but because of labour costs, production has largely shifted to developing countries over the last 35 years or so.

We would like to thank PRORRESINA – Produtos Resinosos, Lda., Casal de Cima, 3330-110 Alvares, Telef./Fax 235 587 102  for their help in the research for this webpage.