Jepson Flora Project: Jepson Interchange    

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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.



David J. Keil, Family Editor and author, except as specified

Annual to tree
Leaves basal or cauline, alternate to whorled, simple to compound
Inflorescence: 1° inflorescence a head, each resembling a flower, 1–many, generally arrayed in cymes, generally subtended by ± calyx-like involucre; flowers 1–many per head
Flowers bisexual, unisexual, or sterile, ± small, of several types; calyx 0 or modified into pappus of bristles, scales, or awns, which is generally persistent in fruit; corolla radial or bilateral (rarely 0), lobes generally (0)4–5; stamens 4–5, anthers generally fused into cylinder around style, often appendaged at tips, bases, or both, filaments generally free, generally attached to corolla near throat; pistil 1, ovary inferior, 1-chambered, 1-seeded, style 1, branches 2, generally hair-tufted at tip, stigmas 2, generally on inside of style branches
Fruit: achene, cylindric to ovoid, generally deciduous with pappus attached
Genera in family: ± 1300 genera, 21,000 species (largest family of dicots): worldwide. Largest family in CA. Also see tribal key to CA genera: Strother 1997 Madroño 44(1):1–28. See glossary p. 25 for illustrations of general family characteristics.



Meredith A. Lane

Subshrubs, glabrous to scabrous or hairy
Stems prostrate or decumbent to ascending or erect, < 3 m, ± striate below, minutely scabrous, yellow-white or gray to red-brown
Leaves alternate, sometimes clustered in axils, entire or toothed, gland-dotted, sometimes gummy, glabrous, minutely scabrous, or tomentose, light to dark gray-green
Inflorescence: heads discoid, in loose to tight clusters, these borne in flat-topped or ± spheric cymes; involucres obconic; phyllaries yellow-white below, texture cartilage-like, tips green; receptacles flat, naked
Flowers yellow; tubes narrowly cylindric, abruptly expanded into larger cylindric throat; sinuses shallow, lobes erect; style branch appendages triangular
Fruit narrowly obconic, light tan, silky-hairy; hairs white, yellow, tan, or light red-tan; pappus of 1–2 series of white, yellowish, or red-tan bristles ± 2 X fruit
Species in genus: ± 10 species: sw North America, Mex
Etymology: (Greek: equal hair-tuft, from flowers)
Reference: [Nesom 1991 Phytologia 70:69–114]


I. menziesii (Hook. & Arn.) G.L. Nesom

Plant < 2 m, mat-forming, rounded or open
Stems prostrate to erect, branched from base or rarely above, glabrous, minutely scabrous, or tomentose, sometimes with stalked glands, yellow-tan, gray, gray-green, or red-brown
Leaves 0.7–4.5 cm, 5–15 mm wide, (ob)ovate to widely spoon-shaped, entire or toothed, gland-dotted or sometimes with stalked glands, glabrous, minutely scabrous, or tomentose, gray-green
Inflorescence: heads in loose to tight clusters of 4–10, these arranged variously; involucres 4.5–10 mm, 2.5–8 mm diam; phyllaries 20–40 in 3–6 series, lanceolate, tips acute, abruptly soft-pointed, green to 1/3–1/2 total length of phyllary, flat
Flowers 12–22
Fruit < 3.5 mm; pappus 3–5 mm, white to tan-white
Chromosomes: 2n=12
Ecology: Sandy soils, coastal and inland
Elevation: < 1200 m.
Bioregional distribution: sw Sacramento Valley, Central Western California, South Coast, Channel Islands, Peninsular Ranges
Distribution outside California: Baja California
Synonyms: I. veneta (Kunth) Greene; Haplopappus v. (Kunth) S.F. Blake
Here treated as 3 strongly intergrading vars.


var. vernonioides (Nutt.) G.L. Nesom

Plants < 1.2 m
Stems erect to decumbent, branched at base, glabrous or scabrous
Leaves clustered in axils, often so dense as to obscure the stem, not fleshy, < 4.5 cm, obovate, ovate, or oblong, glabrous or scabrous
Inflorescence: involucres 8–10 mm, 5–8 mm diam; phyllaries 20–40 in 3–6 series
Flowers 12–22
Ecology: Protected sites on dunes, lagoon shores, marshes
Elevation: < 400 m.
Bioregional distribution: sw Sacramento Valley, Central Western California, South Coast, Channel Islands
Distribution outside California: n Baja California
Synonyms: H. venetus subsp. vernonioides (Nutt.) H.M. Hall
Horticultural information: SUN, DRN, IRR: 5, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24.

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bioregional map for ISOCOMA%20menziesii%20var.%20vernonioides being generated

Retrieve Jepson Interchange Index to Plant Names entry for Isocoma menziesii var. vernonioides
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