Guso is a Bisaya term for a particular type of local seaweed, one of about 500 edible species found in the Philippines, where native seaweeds are commonly consumed. Guso is one of the major products of the waters in the area of Barobo in the area of Surigao del Sur. Seaweeds are farmed by selecting an area in which the desired species are endemic and with a water depth of about half a meter at low tide and at least two meters at high tide, so that seaweeds will not be overexposed to sunlight and air during low tide and will be exposed to enough sunlight penetration during high tide. Seawater temperature should be between 27° and 30°C. Two species of guso are cultured by seaweed growers in the area: Eucheuma spinosum and Eucheuma cottoni. Both are rich in iodine, calcium, antioxidants, vitamins and a natural fiber called alginate. Eucheuma spinosum, or green guso, is usually harvested for local consumption. It has a crunchy texture, but become softer when boiled for a few minutes. It has a naturally salty flavor. Eucheuma cottoni, or red guso or giant guso, is the most commonly cultured guso, and grows much faster than green guso. It can be harvested by pruning all of its branches or by harvesting the entire plant and replacing it with fresh cuttings, which is more often preformed before the plant reaches 1 kg in weight (which takes 45-60 days). The harvested seaweeds are stored in bamboo baskets and sold raw or dried for added value. These seaweeds are often prepared lightly boiled and mixed with spices, served as a side dish to other seafood. Seaweed is one of the most important aquaculture commodities in the Philippines. Seaweed farmers usually enjoy a good harvest from January to June, which are considered peak months for seaweed farming. However, changes in the industry have affected the traditional use of guso. In the 1960s an American seaweed processing company producing carrageenan, a seaweed derivative, transferred from Indonesia to the Philippines. Carrageenan is a gelatin-like extract of guso used as thickener, emulsifier, stabilizer or gelling agent in food, beverages, cosmetics and pharmaceuticals. Today, the edible guso can be found in just in wet markets in the Philippines, usually sold on weekends. Much of the quantity harvested, however, is exported either in raw form (fresh or dried seaweeds) or processed form (carrageenan and kelp powder). There are several reasons why guso is at risk of disappearing. Firstly, with exportations, guso is no longer found in local medium and larger sized grocery stores, and remains on the menu mainly in cafeterias as opposed to larger restaurants. Pollution in local waters has not necessarily killed off the seaweeds, but consumers are unlikely to seek guso from polluted waters or continue farming guso in these areas. Natural disasters, like Typhoon Haiyan, also destroyed a large amount of the nation’s seaweed producing areas. Finally, illegal and destructive fishing activities (the use of dynamite and cyanide) are damaging seaweed-growing areas.