A brown kelp with a large, linear blade that has a pronounced midrib and ruffled margins. It occurs on rocks in the low intertidal and subtidal zones and may be harvested on foot without a boat during very low tides.
Material: Widely used as garden fertilizer. Some people wrap fish in ribbon kelp and then bake it in gravel.
Medicine: Recommended for relieving arthritis. People boil the kelp for five minutes and then soak the arthritic area in the water until the water cools. Blades and stipe can also be placed on steam bath rocks or wrapped around the arthritic area.