Chrysothamnus humilis |
Chrysothamnus greenei |
|
---|---|---|
Truckee green rabbitbrush, Truckee rabbitbrush |
Greene's rabbitbrush |
|
Habit | Shrubs, 10–30 cm; with woody, branched caudices, bark becoming dark gray, fibrous with age. | Shrubs, 10–50 cm; with woody, moderately branched caudices, bark light gray, flaky to fibrous with age. |
Stems | ascending, green, sparsely to densely puberulent, sparsely glandular. |
ascending, green becoming tan, glabrous, resinous. |
Leaves | ascending to spreading; sessile; blades with faint midnerves and pair of collaterals, narrowly elliptic to oblanceolate, 10–30 × 0.7–1.2 mm, flat to sulcate, apices acute (often apiculate), faces moderately puberulent, sparsely stipitate-glandular. |
ascending to spreading; sessile; blades with faint midnerves, linear-filiform, 10–40 × 0.5–2 mm, flat or sulcate, sometimes twisted, margins glabrous or hirtellous, apices acute to apiculate, faces glabrous. |
Involucres | turbinate, 6–10 × 3–4 mm. |
cylindric to turbinate, 5–8 × 1.5–2.5 mm. |
Disc florets | 2–3(–4); corollas 5.5–8 mm, lobes 1–1.7 mm; style branches 2–2.7(–3.4) mm (included in or barely surpassing spreading corolla lobes), appendages 0.8–1.4 mm (lengths about equaling stigmatic portion). |
4–5; corollas 3.7–5.5 mm, lobes 0.8–1.5 mm; style branches 2–2.4 mm (exserted beyond spreading corolla lobes), appendages 0.5–0.8 mm (shorter than stigmatic portion). |
Phyllaries | (12–)14–18 in 3–4 series, ± in vertical ranks, mostly tan, sometimes green-tipped, ovate or oblong to elliptic, unequal, 2.5–7.5 × 1–1.8 mm, chartaceous, outer ± herbaceous wholly or distally, weakly keeled, midveins faint, apices acute to obtuse, faces sparsely puberulent. |
15–20 in 3–4 series, often in vertical ranks or spirals, mostly tan, ± greenish apically, midveins rarely visible, ovate or oblong to elliptic, 1.5–5 × 0.8–1.4 mm, unequal, mostly chartaceous, sometimes ± keeled, apices acuminate to cuspidate (cusp often recurved or falcate), faces glabrous or with a few long, crooked hairs proximally and near margins, resinous. |
Heads | in densely cymiform arrays, often overtopped by distal leaves. |
in densely cymiform arrays (4 cm wide), distal leaves reaching into but not overtopping arrays. |
Cypselae | reddish brown, turbinate, 4–6 mm, densely hairy; pappi tan, 5–7 mm. |
reddish brown, turbinate, 3–4 mm, faces densely hairy; pappi tan, 3.7–5 mm. |
2n | = 18. |
= 18. |
Chrysothamnus humilis |
Chrysothamnus greenei |
|
Phenology | Flowering summer–fall. | Flowering summer–fall. |
Habitat | Sagebrush grasslands, open slopes in deserts, tolerant of alkali | Sandy washes, dry open places in desert |
Elevation | 1400–3100 m (4600–10200 ft) | 1300–2000 m (4300–6600 ft) |
Distribution |
CA; ID; NV; OR; WA
|
AZ; CA; CO; NM; NV; UT; WY
|
Source | FNA vol. 20, p. 189. | FNA vol. 20, p. 189. |
Parent taxa | Asteraceae > tribe Astereae > Chrysothamnus | Asteraceae > tribe Astereae > Chrysothamnus |
Sibling taxa | ||
Synonyms | C. viscidiflorus subsp. humilis | Bigelowia greenei |
Name authority | Greene: Pittonia 3: 24. (1896) | (A. Gray) Greene: Erythea 3: 94. (1895) |
Web links |