Sea Lettuce

Sea lettuce is the common name for the genus Ulva, a group of edible green algae distributed along coastlines worldwide, whose type species Ulva lactuca takes its name from the Latin word for lettuce; the genus also includes species once classified separately as Enteromorpha and known as green nori. Individual blades form a light to dark green, leaflike flattened thallus attached by a disc shaped holdfast and can exceed four hundred millimetres in sheltered growing conditions. Sea lettuce is eaten in Scandinavia, Great Britain, Ireland, China and Japan, where it is called aosa, either raw in salads or cooked in soups, and is high in protein, soluble dietary fibre and minerals, especially iron, though heavy metal contamination at some collection sites poses a health risk; it also feeds marine animals including manatees and sea hares.