Mentzelia veatchiana |
Mentzelia reverchonii |
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Veatch's blazing star, white-stem blazingstar, white-stem stick-leaf |
Reverchon's blazingstar |
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Habit | Plants candelabra-form, (5–)20–50 cm. | Plants biennial or perennial, candelabra-form, perennials with ground-level caudices. |
Stems | solitary, erect, straight; branches distal, distal longest, antrorse, straight to upcurved; hairy. |
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Leaves | blade 24.2–54 × 6.6–29 mm, widest intersinus distance 5.4–13.5(–22.4) mm; proximal oblanceolate to elliptic, margins dentate to pinnate, teeth or lobes 10–20, perpendicular to leaf axis, 1.1–5 mm; distal lanceolate, base not clasping, margins dentate, teeth 8–14, perpendicular to leaf axis, 0.6–3.8 mm; abaxial surface with simple grappling-hook, complex grappling-hook, and occasionally needlelike trichomes, adaxial surface with simple grappling-hook and needlelike trichomes. |
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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 usually toothed, occasionally 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, (9.6–)11.1–14.1(–22) × 2.5–4.2(–5.5) mm, apex acute to rounded, glabrous abaxially; stamens golden yellow, 5 outermost petaloid, filaments narrowly spatulate, slightly clawed, 9.4–13.4(–20) × 2.2–3.7(–5) mm, without anthers, second whorl with anthers; anthers straight after dehiscence, epidermis smooth; styles 8.7–11.4(–13) mm. |
Capsules | clavate, 8–28 × 2–4 mm, axillary curved to 70° at maturity, usually inconspicuously longitudinally ribbed. |
usually cylindric, rarely cup-shaped, 9.4–22 × 6–9.1 mm, length usually more than, occasionally a few slightly less than, 2 times diam., base tapering, 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 5–7 per cell. |
2n | = 54. |
= 18. |
Mentzelia veatchiana |
Mentzelia reverchonii |
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Phenology | Flowering Mar–Jun. | Flowering Apr–Oct. |
Habitat | Loamy to sandy soils, grasslands, desert scrub, oak-pine woodlands. | Grasslands on eroded riverbanks, roadsides, roadcuts, sparsely vegetated hillside slopes, sandy, gravelly, clayey, occasionally gypsum soils. |
Elevation | 200–2500 m. [700–8200 ft.] | 50–600 m. [160–2000 ft.] |
Distribution |
AZ; CA; NV; OR
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CO; NM; OK; TX; Mexico (Coahuila, Nuevo León) |
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.) |
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Source | FNA vol. 12, p. 543. | FNA vol. 12, p. 519. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | M. albicaulis var. veatchiana | M. pumila var. reverchonii, M. hintoniorum, Nuttallia reverchonii |
Name authority | Kellogg: Proc. Calif. Acad. Sci. 2: 99, fig. 28. (1863) | (Urban & Gilg) H. J. Thompson & Zavortink: Wrightia 4: 24. (1968) |
Web links |