The lawn of the intertidal zone has fronds that are short, usually less than 5 centimetres tall, and stiff, like tiny bristles. They grow in dense, crowded mats, covering the rocks in a greenish-red carpet. From a distance, it looks like moss or short grass. Up close, it is a forest of tiny, branching seaweeds, each one anchored firmly to the rock. It is the alga of the low growth, the one that covers the rock like a green carpet. What makes it special is the density. The turf algae grows in such dense mats that it creates its own microclimate. The mat traps moisture at low tide, keeping the rocks damp. It traps sediment, building up a layer of fine silt. It provides shelter for a whole community of tiny invertebrates, crustaceans, worms, snails, that live in the spaces between the fronds. It is the alga of the community, the one that creates a home for others. The turf algae is tough. Its fronds are stiff and wiry, made of a strong, flexible material that can withstand the pounding of the waves. It is also hard to dislodge, its holdfast grips the rock like glue. You can scrape at it with your fingernail and it will not come off. It is the alga of the tough surface, the one that holds on when others let go. Biologically, the turf algae is a red alga. It reproduces by releasing spores from specialised structures on its fronds. The spores are released into the water, carried by the currents, and settle on nearby rocks to grow into new plants. To find turf algae is to find the greenish-red carpet on the rock. It is short, dense, bristly, the lawn of the intertidal zone. It does not stand tall. It does not wave in the current. It just covers the rock, low and tough, providing a home for the small creatures of the tide. It is the alga of the low places, the one that holds the rock together.