CYPERACEAE

SEDGE FAMILY

Raymond Cranfill, except as specified

Annual or perennial herb, often rhizomed, often of wet open places, generally monoecious; roots fibrous, hairy
Stem generally 3-sided
Leaves often 3-ranked; sheath generally closed; ligule generally 0; blade (0) various, parallel-veined
Inflorescence: spikelets variously clustered; flowers generally sessile in axil of flower bract
Flower small, generally wind-pollinated; perianth 0 or bristle-like; stamens generally 3, anthers attached at base, 4-chambered; ovary superior, 1-chambered, 1-ovuled, style 2–3-branched
Fruit: achene, generally 3-sided
Genera in family: ± 110 genera, 3600 species: worldwide, especially temp
Reference: [Tucker 1987 J Arnold Arbor 68:361–445]
Difficult: taxa differ in technical characters of inflorescence and fruit.

ERIOPHORUM

COTTON GRASS

Perennial
Stem leafy, solid
Leaves sheathing; uppermost often bladeless
Inflorescence subtended by 1–several, leaf- or scale-like bracts; spikelets terminal, solitary, or in head-like clusters; flower bracts spiraled
Flowers bisexual; perianth bristles 6–many, > flower bracts, persistent, often greatly elongating; stamens 3; style 3-branched
Fruit ± flat or 3-sided
Species in genus: ± 20 species: especially n temp (1 s Africa)
Etymology: (Greek: wool-bearing)

Native

E. gracile W.D.J. Koch

Stem 30–60 cm, rounded, from spreading rhizome
Leaves 2–30 cm, 3-sided; basal 0 at flower
Inflorescence: spikelets 2–5
Flower: perianth bristles many, not barbed, white
Chromosomes: 2n=30,38
Ecology: Wet meadows, bogs
Elevation: generally > 2000 m.
Bioregional distribution: Northwestern California, Cascade Range, n&c High Sierra Nevada
Distribution outside California: circumboreal
Formerly in SnFrB
Horticultural information: TRY.