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Subshrub; herbage glabrous, minutely scabrous, sessile- or stalked- glandular, long-soft-hairy, or tomentose.
Stem: prostrate to erect, ± striate below, yellow-white or gray to red-brown, glabrous or variously hairy, often dotted with sessile resin glands.
Leaf: alternate, sometimes clustered in axils, entire, toothed, or pinnately lobed, gland-dotted, sometimes gummy-resinous, light to dark gray-green.
Inflorescence: heads discoid, in loose to tight cyme-like clusters, these borne at branch tips or in ± flat-topped or panicle-like 2° clusters; involucre obconic; phyllaries yellow-white proximally, cartilaginous, tips green; receptacle flat, epaleate.
Flower: corolla yellow; tube narrowly cylindric, abruptly expanded into larger cylindric throat; lobes short, 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, ± yellow, or red-tan bristles ± 2 × fruit.
16 species: sw North America, Mex. (Greek: equal hair-tuft, from flowers) [Nesom 2006 FNANM 20:439–445] Plants from s San Diego Co. with pinnately lobed leaves resemble Isocoma tenuisecta Greene, not in CA, but are more densely hairy.
Unabridged references: [Nesom 1991 Phytologia 70:69–114]

Key to Isocoma

1. Phyllary tip swollen, with a prominent linear to widely elliptic resin gland (resin glands rarely >= 2), often with additional minute dot-like resin glands

2. Lvs all entire or proximal leaves toothed or lobed ..... I. acradenia (2)

3. Phyllary tips rounded and not or occasionally weakly soft-pointed; flowers 18–24 ..... var. acradenia

3' Phyllary tips blunt to acute (inner ones), abruptly soft-pointed; flowers 20–27 ..... var. bracteosa (2)

2' Lvs all toothed or pinnately lobed

4. Fls 10–13; phyllaries minutely awn-tipped ..... I. arguta (2)

4' Fls 12–27; phyllaries rounded and not or minutely awn-tipped ..... I. acradenia (2)

5. Fls 20–27; phyllaries abruptly soft-pointed ..... var. bracteosa (2)

5' Fls 12–20; phyllaries rounded and not awn-tipped or very weakly awn-tipped ..... var. eremophila

1' Phyllary tip dotted with minute resin glands (rarely with >= 1 weakly developed larger resin glands)

6. Fls 10–13; phyllaries minutely awn-tipped ..... I. arguta (2)

6' Fls 15–28; phyllaries acute, not at all awn-tipped, or with weakly developed projection at tip ..... I. menziesii

7. Lf oblong-oblanceolate to widely obovate, coarsely serrate, ± thick, fleshy; stem and leaves glabrous, glandless — plants decumbent or prostrate ..... var. sedoides

7' Lf linear, narrowly oblong, or oblanceolate to obovate, entire, toothed, or shallowly lobed, not fleshy (or if fleshy, at least stem long-soft hairy); stem and leaves glabrous to long-soft hairy, tomentose, or glandular

8. Herbage stalked-glandular, without nonglandular hairs or finely and closely ± gray cobwebby-tomentose

9. Plant prostrate or decumbent to ± erect; leaves 2–4 mm wide; heads in ± flat-topped or panicle-like cluster; fruit generally 2.3–3.6 mm; s SCo, s ChI, s PR ..... var. decumbens (2)

9' Plant strictly erect; leaves 4–10 mm wide; heads in ± flat-topped cluster; fruit generally 4–5 mm; s SnFrB, n SCoRI ..... var. diabolica (2)

8' Herbage not prominently glandular, otherwise glabrous to long-soft-hairy or tomentose

10. Plant prominently long-soft-hairy or tomentose

11. Herbage finely and closely gray tomentose; leaves narrowly oblanceolate, entire or few-toothed; stems decumbent to erect ..... var. decumbens (2)

11' Herbage with long, spreading ± thick-based hairs; leaves oblanceolate or oblong-oblanceolate, at least proximal leaves toothed along most of margin; stems generally erect ..... var. vernonioides (2)

10' Plant glabrous or slightly hairy, sometimes resinous

12. Lvs entire or few-toothed at tip ..... var. menziesii

12' At least proximal leaves serrate

13. Corolla 6–7 mm; fruit (3.8)4.5–5 mm ..... var. diabolica (2)

13' Corolla 5–7 mm; fruit 2.3–3.6 mm ..... var. vernonioides (2)

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Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].
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