Cotton Grass

Cotton Grass Eriophorum angustifolium, is a perennial (meaning re-occuring year after year) plant native to the blanket bogs of the British isles and found all over the northern fells. It often covers large expanses of moorland turning them white with its characteristically cotton-like seed heads, which can be an amazing sight in the height of summer.

It is a member of the Sedge family, all of which resemble grasses in some way but are differentiated by the sharp edges on the stems, botanists have a saying for this; “sedges have edges” it is also known as ‘bog cotton’.

White downy seeds

The seed heads of Cotton grass grow about 40cm high on the plant and produce fine white hairs which are attached to the edges of the sedge, these will sit, waiting, on the seed head until there is a sufficiently strong enough breeze to lift them and carry them further afield to germinate.

The days when this happens are usually dry and warm with a firm breeze and it can be a very magical and timeless experience to walk waste high through the rushes across the moors when the air is full of thousands of white downy seeds lifting off and drifting over the horizon.

Wave and bow with the wind

The seed heads also wave and bow with the wind and usually the places they grow are not parts of the moor that you will walk across if you can avoid it. This is because Cotton grass prefers very boggy moors with acidic soils, the type of nutrient poor, waterlogged bogs that Sphagnum moss and Sundews also like.

The downy seed heads of Cotton grass are a favourite food of several upland species, Black Grouse will gather to gorge themselves on the seed heads, venturing out far from their usual woodland territories on to the open moors.

Important species

Several species of insect also rely upon Cotton grass as a food plant, the caterpillars of the Large Heath Butterfly feed on the seed heads and as they are endangered species which are only found in a few places in the north of England large areas of Cotton grass are therefore very important for their continued existence here.

The cotton-bud-like seeds were once important to humans as well, the dried out fluff would be used by shepherds as candlewick and several Ray Mears style survival manuals recommend it as tinder for lighting fires in an emergency. Nowadays it is most useful as a marker, a kind of white flag to indicate where bogs are and that you should really find a path if you don’t want to end up stuck waist deep in a swamp!

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