Grasses List 

COMMON COTTON-GRASS

BOG COTTON

Eriophorum angustifolium

Sedge Club- & Spike-Rush Family [Cyperaceae]

Flowers:
month8apr month8april month8may

Pappus: pappusZpossible (white, simple)
pappus8may pappus8Jun pappus8June pappus8Jul pappus8July

category
category8Grasses
status
statusZnative
flower
flower8white
inner
inner8cream
type
typeZspiked
stem
stem8round
stem
stem8triangular

17th July 2013, White Hill, Marsden, West Pennines. Photo: © RWD
2012 saw the wettest rainiest year since records began. The year after, 2013, had the best summer for over 10 years. These two conditions compounded together to a produce a profusion of Cotton-grass covering the peatland moors painting them white like a sprinkling of snow for tens of miles around. Although Blackstone Edge on horizon, this is White Hill. It is now patently obvious why it has this name, not so obvious at all in previous years.


15th July 2013, Wimberry Moss, Chew Brook, Greenfield, Lancs. Photo: © RWD
On Wimberry Moss, the Wimberries (aka Bilberry) not obvious in a sea of Bog Cotton. Alphin Pike in near distance.


15th July 2013, Wimberry Moss, Chew Brook, Greenfield, Lancs. Photo: © RWD
Grows to 75cm high on acid uplands in wet peaty moors.


15th July 2013, Wimberry Moss, Chew Brook, Greenfield, Lancs. Photo: © RWD
Normally drooping downwards but caught in the wind, the multiple flower-head clusters wave like flags.


15th July 2013, Wimberry Moss, Chew Brook, Greenfield, Lancs. Photo: © RWD
A single stem can have between three to seven flower spikes on short stalks. They are covered in hairs when in fruit.


15th July 2013, Wimberry Moss, Chew Brook, Greenfield, Lancs. Photo: © RWD
Three flower spikes on this specimen, all in fruit.


15th July 2013, Wimberry Moss, Chew Brook, Greenfield, Lancs. Photo: © RWD
Like sedges, they have an upright bract reaching above the fruiting flowers, but here bent over by the wind.


15th July 2013, Wimberry Moss, Chew Brook, Greenfield, Lancs. Photo: © RWD
Close-up of how the flower heads emerge atom the stem.


15th July 2013, Wimberry Moss, Chew Brook, Greenfield, Lancs. Photo: © RWD
The stem is triangular, at least near the top, and is finely ribbed/fluted.


Not to be semantically confused with : Cotton Thistle (Onopordum acanthium) [a plant with similar name belonging to a differing family]

Can be mistaken for : other Cotton-grasses such as Broad-leaved Cotton-grass (Eriophorum latifolium) but that only grows on limy soils such as Fens never on acid soils, although it does grow on peat as long as there is lime underneath to neutralise the acid, or the much rarer Slender Cotton-grass (Eriophorum gracile).

Some similarities to : Hare's-Tail Cotton-Grass (Eriophorum vaginatum) but that has only one flower-spike, whereas Common Cotton-grass has several (between 3 and 7).

Uniquely identifiable characteristics

Distinguishing Feature : When in fruit has multiple flower spikes with hairy pappuses and growing on acidic wet upland peat areas.

No relation to : Cottonweed (Achillea maritima) [a plant with similar name belonging to the Daisy & Dandelion Family (Asteraceae)] nor to North-American Cottonwood (Populus deltoides) [a tree to 40m] nor to Cotoneasters nor to Cotton Thistle (Onopordum acanthium) [a thistle].

Although superficially similar to some grasses (Poaceae, Cotton-grasses are in the Sedge Family (Cyperaceae).

The flower spikes first have cream coloured anthers protruding from during April to May after which the hairy fruiting head develops in June to last two or three months before the seeds on the hairs are blown to pastures new.


  Eriophorum angustifolium  ⇐ Global Aspect ⇒ Cyperaceae  

Distribution
 family8Sedge Club- & Spike-Rush family8Cyperaceae

 BSBI maps
genus8Eriophorum
Eriophorum
(Cotton-Grasses)

COMMON COTTON-GRASS

BOG COTTON

Eriophorum angustifolium

Sedge Club- & Spike-Rush Family [Cyperaceae]