In the cold seas off Hokkaido, Japan's northernmost island, a brown algae known as kombu or kelp, grows in a dense underwater forest. Floating on the water in small skiffs, men and women cut the kombu free using razor-sharp knives that are attached to long bamboo poles. As the kombu floats to the surface it is gathered with wooden rakes and placed in the boats. Once back on land, the kombu is laid out to dry slowly and naturally in the sun. 