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Jepson Interchange (more information)
©Copyright 1993 by the Regents of the University of California

  • Up-to-date information about California vascular plants is available from the Jepson eFlora.



James C. Hickman

Annual to trees, some dioecious
Stem: nodes often swollen
Leaves simple, basal or cauline, alternate, opposite, or whorled, generally entire; stipules 0 or obvious and fused into a generally scarious sheath around stem
Inflorescence: small cluster, axillary or arrayed in cymes or panicles; involucres sometimes subtending 1–many flowers
Flower generally bisexual, small, ± radial; perianth generally 5–6-lobed, base ± tapered, often jointed to pedicel; stamens 2–9, often in 2 whorls; ovary superior, styles generally 3, generally fused at base
Fruit: achene, generally enclosed by persistent perianth, generally 3-angled, ovoid, and glabrous
Genera in family: 50 genera, 1100 species: worldwide, especially n temp; some cultivated for food (Fagopyrum ; Rheum , rhubarb; Rumex , sorrel) or ornamental (Antigonon , coral-vine; Muehlenbeckia ; Polygonum )
Reference: [Ronse Decraene & Akeroyd 1988 Bot J Linn Soc 98:321–371; Reveal et al. 1989 Phytologia 66(2–4):83–414]
Treatments of the 15 eriogonoid genera are based on the monographic work of James L. Reveal, who is gratefully acknowledged.



Annual to shrub
Leaves generally ± basal (clustered on low stems or cauline), petioled, generally ± tomentose below (often shedding above); stipule 0
Inflorescence openly cyme-like, umbel-like, or head-like, generally ± scapose; bracts (any whorled, leaf-like structures on inflorescence) 3–many per node, leaf-like to scale-like; involucres generally 1 per node, generally ± obconic, lobes (or short teeth) generally 3–10, generally erect; flowers generally many per involucre, pedicelled
Flower: perianth white, yellow, or red, lobes 6, generally ± oblong to obovate; stamens 9
Fruit brown to black, glabrous to hairy
Species in genus: ± 250 species: North America
Etymology: (Greek: woolly knees, from hairy nodes of some)
Reference: [Reveal 1989 Phytologia 66:295–414]
Largest dicot genus in CA; apparently currently differentiating; many taxa ± indistinct. Better habitat data needed. Many are excellent bee fodder
Horticultural information: Most are attractive and easy to grow with good drainage.


E. nudum Benth.

[Group 4] Perennial, 10–200 cm
Leaves basal or ± spaced on lower stem; blade 10–70 mm, oblanceolate to ovate, generally tomentose (especially below)
Inflorescence cyme- to head-like; axes glabrous, sometime wider below major nodes; bracts scale-like (lowest sometimes leaf-like); involucres 1–10 per cluster, 2–5 mm, teeth 5–8
Flower: perianth 1.5–4 mm, white, yellow, or red, subglabrous, stalk-like base 0
Fruit 1.5–3.5 mm, glabrous
Ecology: Abundant. Dry open places
Elevation: < 3800 m.
Bioregional distribution: California (except San Joaquin Valley, South Coast, Channel Islands, Modoc Plateau, Sonoran Desert)
Distribution outside California: to Washington, Nevada, nw Mexico
Varieties difficult, intergrading.


var. pubiflorum Benth.

Leaves basal, 10–40 mm, becoming ± glabrous above; margins flat
Inflorescence slender, glabrous; involucres 3–10 per node, 2–5 mm, generally glabrous
Flower: perianth 2.5–3 mm, white or pale yellow, obviously hairy
Chromosomes: n=20
Ecology: Common. Dry flats, slopes
Elevation: 50–2000 m.
Bioregional distribution: Northwestern California, Cascade Range, Sierra Nevada, Sacramento Valley, San Francisco Bay Area, Mojave Desert
Distribution outside California: s Oregon, w Nevada
Intergrades with vars. oblongifolium & westonii
Horticultural information: SUN, DRN: 1, 2, 4, 5, 6, 7, 14, 15, 16, 17, 24.

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bioregional map for ERIOGONUM%20nudum%20var.%20pubiflorum being generated
N.B. The distribution depicted here differs from that given in The Jepson Manual (1993)

Retrieve Jepson Interchange Index to Plant Names entry for Eriogonum nudum var. pubiflorum
Retrieve dichotomous key for Eriogonum
Overlay Consortium of California Herbaria specimen data by county on this map
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