Irish moss (Chondrus crispus) is a small seaplant that looms large in the make-up of many of our favourite foods and useful products. When we consume ice cream, chocolate milk, salad dressings, beer, or use insect sprays, water-based paints, shampoos, toothpaste or cosmetics, we are almost certain to be using carrageenan, a starch-like, non-caloric substance extracted from Irish moss. Irish moss is a perennial plant with many branches near the top. It ranges in colour from yellowish green to brown to reddish purple, and grows attached to rocks to heights of three to seven inches. It is found from the low tide mark to approximately 30 feet of water.
There are two methods of harvest: by drag rakes or by gathering storm-tossed moss along the shoreline. The harvest is taken by drag rakes towed behind boats. Large quantities of Irish moss, sometimes mixed with Furcellaria, are washed ashore during gale force winds. This storm-tossed moss can be gathered either by picking it up from the shore or scooping it from the tidal wash with handrakes or with baskets towed by horses. Prince Edward Island has a long established history of seaplant harvest. On Prince Edward Island, the industry is centred on the western shore of Prince County, where the largest production of Irish moss is harvested and local buyers have drying and packaging plants.