Mentzelia veatchiana |
Mentzelia oreophila |
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Veatch's blazing star, white-stem blazingstar, white-stem stick-leaf |
Argus blazingstar, mountain loving blazing star |
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Habit | Plants candelabra-form, (5–)20–50 cm. | Plants perennial, bushlike, with subterranean caudices. |
Stems | multiple, erect, straight; branches distal or along entire stem, distal longest or all ± equal, antrorse, upcurved; hairy. |
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Leaves | blade 17–103 × 7.6–41.2 mm, widest intersinus distance 5.1–35.3 mm; proximal oblanceolate to elliptic, margins serrate, teeth 6–22, slightly antrorse, 0.4–5.3 mm; distal elliptic, lanceolate, or deltate, base clasping, margins serrate, teeth 6–16, slightly antrorse, 0.5–4.2 mm; abaxial surface with complex grappling-hook trichomes, adaxial surface with complex grappling-hook and needlelike trichomes, both surfaces green, moderately hairy. |
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Basal leaves | persisting; petiole present or absent; blade linear-lanceolate, margins deeply to shallowly lobed. |
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Cauline leaves | petiole absent; blade ovate-lanceolate to lanceolate, to 17 cm, margins usually deeply lobed to dentate, rarely entire. |
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Bracts | usually green with prominent white base usually conspicuously extending outwards from midvein, rarely green, usually ovate, rarely lanceolate, 3.3–6.2 × 1.5–3.2 mm, width 1/4–7/8 length, not concealing capsule, margins usually 3–7-lobed, rarely entire. |
margins entire. |
Flowers | sepals 2–5 mm; petals red to orange proximally, orange to yellow distally, 4–7(–10) mm, apex retuse; stamens 20+, 3–7 mm, filaments monomorphic, filiform, unlobed; styles (3–)3.5–6 mm. |
petals golden yellow, 7–14.5(–16.2) × 1.7–5.2 mm, apex rounded, glabrous abaxially; stamens golden yellow, 5 outermost petaloid, filaments narrowly spatulate, slightly clawed, 5.3–11.1(–15.4) × 0.6–4.4 mm, with anthers, second whorl with anthers; anthers twisted after dehiscence, epidermis smooth; styles 3.8–8.1 mm. |
Capsules | clavate, 8–28 × 2–4 mm, axillary curved to 70° at maturity, usually inconspicuously longitudinally ribbed. |
cup-shaped, 5.8–9 × 5.2–8.8 mm, base rounded, not longitudinally ridged. |
Seeds | 15–35, in 2+ rows distal to mid fruit, tan, dark-mottled, usually irregularly polygonal, occasionally triangular prisms proximal to mid fruit, surface tuberculate under 10x magnification; recurved flap over hilum absent; seed coat cell outer periclinal wall domed, domes on seed edges more than or equal to 1/2 as tall as wide at maturity. |
coat anticlinal cell walls straight, papillae 6–17 per cell. |
2n | = 54. |
= 22. |
Mentzelia veatchiana |
Mentzelia oreophila |
|
Phenology | Flowering Mar–Jun. | Flowering Feb–Oct. |
Habitat | Loamy to sandy soils, grasslands, desert scrub, oak-pine woodlands. | Sparsely vegetated slopes, roadcuts, loose, rocky and sandy limestone soils. |
Elevation | 200–2500 m. [700–8200 ft.] | 400–1600 m. [1300–5200 ft.] |
Distribution |
AZ; CA; NV; OR
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CA; NV
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Discussion | Mentzelia veatchiana is the most common and widely distributed hexaploid species in sect. Trachyphytum. It exhibits considerable morphological variation and can be difficult to distinguish from M. montana in northern California. Like the larger-flowered M. pectinata, M. veatchiana has interfertile populations with petal colors ranging from orange to yellow (J. E. Zavortink 1966). When bearing orange petals, M. veatchiana is easily distinguished from other species. Reports of M. veatchiana from Utah are based on specimens treated here as M. montana. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Mentzelia oreophila is found in Inyo, Riverside, and San Bernardino counties, California, and Clark, Esmeralda, Lincoln, and Nye counties, Nevada. The California populations have a smaller stature than those in Nevada, and phylogenetic analysis indicated that the species is potentially polyphyletic. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 543. | FNA vol. 12, p. 510. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | M. albicaulis var. veatchiana | |
Name authority | Kellogg: Proc. Calif. Acad. Sci. 2: 99, fig. 28. (1863) | J. Darlington: Ann. Missouri Bot. Gard. 21: 175. (1934) |
Web links |