Sedge - Cyperaceae Family

Peter W. Ball
Perennial herb, erect. Stem: cylindric, solid. Leaf: basal and cauline; ligule present; blade ± scabrous on keel or angles. Inflorescence: 1, terminal, ± umbel-like [head-like or spikelet 1]; inflorescence bracts 1–several, leaf- or scale-like; spikelets several [1]; flower bracts spiraled, > 10, ovate, membranous, glabrous, tip entire. Flower: bisexual; perianth bristles 10–25, >> fruit, generally > flower bracts, >> flower bracts in fruit, ± straight, barbs 0; stamens 3; style 3-branched. Fruit: 3-sided, ± flat.
± 25 species: northern temperate. (Greek: wool-bearing) Eriophorum crinigerum moved to Calliscirpus (Gilmour et al. 2013); see note under family. [Jepson]

Cotton grasses favor wet bogs, roadsides, and tundra. There are over one dozen Eriophorum species and subspecies distributed throughout Alaska alone. Distribution decreases markedly in the southern range of the Pacific Northwest. Only one species, E. gracile, reaches from Alaska to California. [Schofield]

Local Species;

  1. Eriophorum angustifolium - narrow-leaved cotton-grass [E-flora]
  2. Eriophorum chamissonis - Chamisso's cotton-grass [E-flora][TSFTK]
  3. Eriophorum gracile - slender cotton-grass [E-flora]
  4. Eriophorum virginicum - tawny cotton-grass [E-flora]

1 Perianth bristles numerous, at least 10 mm long, without barbs

2 Each inflorescence consisting of a single spikelet (perianth bristles generally 13-15 mm long, usually white, sometimes brownish or reddish) ...................................E. chamissonis, pI. 617
2 Most inflorescences consisting of at least 2-3 spikelets

3 Inflorescence with a single leaflike bract beneath it (high montane) ......... E. gracile


3 Inflorescence with 2 or more leaflike bracts beneath it
4 Spikelets nodding, with peduncles to more than 3 cm long; perianth bristles white (montane, mostly above 3000 ft., 910 m) ......... E.angustifolium (E. polystachion of some references)


4 Spikelets mostly upright, with peduncles not more than about 1.5 cm long; perianth bristles brownish (apparently introduced in a few places) ............... E. virginicum


Eriophorum gracile "W.D.J. Koch ex Roth, Slender Cottongrass. Bogs and open swamps. Circumboreal, in North America from NL (Labrador) west to AK, south to s. PA (Rhoads & Klein 1993), s.NJ, w. MD (C. Frye, pers comm. 2000), DE (McAvoy & Bennett 2001), OH, IN, IL, MN, CO, UT, NV, and CA." [Weakley FSMAS]

Sedge family members should not be used medicinally without medical supervision. Properties and effectiveness are variable with species.[Schofield]

Edible Uses

Other Uses

Medicinal Uses


"Moist tundra occupies the foothills and lower elevations of the Alaska Range as well as extensive areas on the Seward and Alaska peninsulas, the Aleutian Islands, and the islands of the Bering Sea. The type varies from almost continuous and uniformly developed cottongrass (Eriophorum) tussocks with sparse growth of other sedges and dwarf shrubs to stands where tussocks are scarce or lacking and dwarf shrubs are dominant. Over wide areas in Arctic Alaska, the cottongrass tussock type is the most widespread of all vegetation types." [Viereck ATS]

Narrow-Leaved Cotton-Grass - Eriophorum angustifolium

Family: (Sedge family) [E-flora]
Other Names: (tall cottongrass)[E-flora]


Eriophorum angustifolium is a PERENNIAL growing to 0.6 m (2ft) by 1 m (3ft 3in). It is hardy to zone (UK) 4 and is not frost tender. It is in flower from May to June, and the seeds ripen from Jul to August. The flowers are monoecious (individual flowers are either male or female, but both sexes can be found on the same plant) and are pollinated by Wind. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and can grow in heavy clay soil. Suitable pH: acid soils and can grow in very acid soils. It can grow in semi-shade (light woodland) or no shade. It prefers wet soil and can grow in water. [PFAF]

General: Perennial herb from creeping rhizomes; stems 10-90 cm tall. [IFBC-E-flora]
Leaves: Sheaths brownish to purplish or blackish, persistent; blades 2-6 (8) mm wide, flat but becoming narrow and folded toward the tips, the uppermost ones equalling or exceeding the sheaths. [IFBC-E-flora]
Flowers: Spikes 2 to 10, terminal, erect, at least some of them pendulous, egg-shaped and 1-2 cm long in flower, 2-4 cm long in fruit; anthers 2.5-4 mm long; involucral bracts several, unequal, 2 or more of them evidently leaflike, the longest ones equalling or surpassing the inflorescence. [IFBC-E-flora]
Fruits: Scales brownish or blackish-green, egg-shaped to lanceolate, appressed to ascending, 1-ribbed, pointed, the slender midribs not reaching the tips; perianth bristles numerous, whitish, creamy-white to tawny, many times longer than the achenes; achenes blackish, 2-3 mm long, broadly lanceolate to egg-shaped. [IFBC-E-flora]

Habitat / Range
Bogs, fens, marshes, shorelines and wet meadows in all vegetation zones; common throughout BC; circumpolar, N to AK, YT and NT, E to NF and S to NH, NC, TN, IA, NE, NM, ID and OR; Eurasia. [IFBC-E-flora]

Origin Status: Native [E-flora]

USDA Flower Colour: Yellow
USDA Blooming Period: Late Spring
USDA Fruit/Seed characteristics:

Colour: Brown
Present from Summer to Fall [USDA-E-flora]

Edible Uses

Other Uses

Medicinal Uses


The stems of the non-flowering tall cotton grass are considered to be female and may be eaten from early spring until the ducks leave in the fall. The lower stems are gathered while green and eaten raw, especially by the children. Adults occasionally eat the lower stems raw and often gather the tops into loose bundles for future use. However, more commonly, the flowerless stems are collected in bundles in the late fall after they have completed their growth and have turned gray white. They are thoroughly dried on the top of a house or storage shed and split lengthwise to be used as the warp and weft in weaving mats .This plant fiber makes particularly good mats, socks. coarse sacks , and formerly shrouds since the fiber can endure repeated moistening and drying without breaking. A strip of the dried stem is also placed between the waterproof seams of a skin boot in order to inhibit leakage. When a girl is secluded during her first menses. she is permitted to eat the stems of the female plant. These may be given to her raw or after being cooked in hot water. When tall cotton grass is cooked. the old people say that it tastes just like fresh fish . Tall cotton grass stems. when eaten raw , are considered to be a good medicine for persons in poor general health. By eating the lower stems of female plants, one soon may expect to regain good health.
Heller (1953 . p. 131) describes tall cotton grass as being used along the lower Kuskokwim River and notes that mice collect the roots for their winter food: just before freeze-up the people search for these mouse caches and remove the roots . The black outside layer of the root is removed by pouring boiling water over it, and the roots are then eaten with seal oil. The same collecting technique is recorded for Carex sp.: a fish is sometimes substituted for the roots that are removed in order that the mouse may survive the winter (Anderson, 1939, p . 715) .[Oswalt Eskimo]

But cottongrass heads were a crop on the Isle of Skye, gathered usually by the children. Dried, they were used to stuff pillows and quilts (Swire. 1961) (St Bride lined the bed of Christ with cotton-grass, even though the birth of Christ occurred in mid-winter (Swire. 1964)). Stuffing pillows must have been a tedious task, for when the heads were used whole they would be lumpy in a pillow, but the trick is to remove the tough base and use only the down. It can be spun like cotton, but the fibres are more brittle than those of cotton, so not so useful. Candle and lamp wicks used to be made of the down (Johnson), while children often use them like powder puffs (Bairacli-Levy).[DPL Watts]

Requires boggy conditions or a pond margin and an acid soil[1, 162]. Grows well in heavy clay soils. Quite invasive.[PFAF]

"The high annual rainfall and cold winters at the higher latitudes also favor perennial cool season grasses and sedges over some of the annual species that occur farther south. The acidic conditions may also be augmented by accumulations of sphagnum moss on the bog surface. Plants include round leaf sundew (Drosera rotundifolia), cottongrass (Eriophorum spp.), cloudberry (Rubus chamaemorus), bog laurel (Andromeda polifolia), bog bean (Menyanthes trifoliate), and Cusick’s sedge (Carex cusickii)." [Apostol RPNW]

Arsenic Hyperaccumulator: "Accumulator plants uptake and translocate arsenic to shoots without toxic symptoms (Ross and Kaye 1994; Prasad 2008) . Mention has been made of “root accumulators”, which have higher arsenic concentration in roots than in shoots, Carex rostrata, Eriophorum angustifolium, Phragmites australis, and Salix sp (Stoltz and Greger 2002a, b, 2006a, b, c) and also it has been pointed out that spontaneous vegetation species covered the large toxic mine spill contaminated areas in Spain (Del Rio et al. 2002)." Plants on mine talings yeilded 152 (mg As kg-1 soil) [Lichtfouse ECSW]

Fe Resistance: "The species with the highest resistance were almost exclusively monocots (e.g. Eriophorum angustifolium, Carex echinata), while the most sensitive species were all dicots (e.g. Rumex hydrolapathum, Epilobiumhirsutum). The higher Fe resistance ofmonocots may result from two traits: a more efficient detoxification system which reduces direct Fe toxicity and lower growth rates which minimize indirect toxicity effects on mineral nutrition. Iron resistance and relative growth rates were negatively correlated" [Prasad HMSP]

Seed - sow in situ in spring in a moist soil in light shade. Germination usually takes place within 2 - 6 weeks at 15°c[200]. If the seed is in short supply it can be sown in pots in a cold frame. Place the pots in a try of water to keep the compost moist. When large enough to handle, prick the seedlings out into individual pots and plant them out in the summer. Division in spring or autumn. Very easy, the divisions can be replanted direct into their permanent positions.[PFAF]



Page last modified on Thursday, January 24, 2019 3:12 AM