Hare’s tail cottongrass is the most common and probably the most easily recognised member of the Cyperaceae with white woolly spikelets in Estonia. All one needs to know is that it is the only cotton grass with just one woollen tuft at the top of the stem. They grow in damp places, where there is less or more of peat moss. In terms of cottongrass, hare’s tail cottongrass definitely plays the most important role in the formulation of peat. This means that in some ways, it also plays an important role for people.