Sea Lettuce is a form of green algae common all around the world. It looks very similar to commercially grown lettuce although is an entirely different species of plant. Sea Lettuce will initially grow flat but the leaves will begin to ruffle with age. Individual plants will typically grow up to 19 inches (50 cm) in length and are bright green when wet. The structure of the leaves is thin and delicate and the plant will often resemble green cellophane.
The algae will often cover rocks in tidal areas in thick, slippery carpets. Like similar algae, it uses a holdfast to connect to the underlying rock.
Sea Lettuce is one of the most common green algae in the world and can thrive on rocky beaches and upper tidal areas where it is frequently exposed to air and direct sunlight. It is present throughout the year in coastal areas of the Pacific Northwest.