Mentzelia laevicaulis

(Douglas) Torrey & A. Gray

Fl. N. Amer. 1: 535. 1840.

Common names: Giant blazingstar
WeedyIllustratedEndemic
Basionym: Bartonia laevicaulis Douglas in W. J. Hooker Fl. Bor.-Amer. 1: 221, plate 69. 1832
Treatment appears in FNA Volume 12. Treatment on page 514. Mentioned on page 501, 505.

Plants biennial or perennial (in rosette stage), bushlike. Stems solitary, erect, straight; branches distal or along entire stem, proximal or distal longest, antrorse, upcurved; hairy or glabrescent. Leaves: blade 17.4–196 × 6.7–40.4 mm, widest intersinus distance 2.4–24.6 mm; proximal oblanceolate, lanceolate, or elliptic, margins pinnate, lobes 14–44, slightly antrorse, 2.5–8.9 mm; distal lanceolate, base clasping or not, margins pinnate, lobes 6–42, slightly antrorse, 2.1–13.8 mm; abaxial surface with simple grappling-hook, complex grappling-hook, and needlelike trichomes, adaxial surface with needlelike trichomes. Bracts: margins entire or pinnate. Flowers: petals golden yellow, 23.5–70 × 3–17.3 mm, apex acute, glabrous abaxially; stamens golden yellow, 5 outermost not petaloid, filaments linear to narrowly elliptic, not clawed, 17.7–55 × 0.5–2 (–2.5) mm, with anthers, second whorl with anthers; anthers straight after dehiscence, epidermis smooth; styles 20.4–57 mm. Capsules cupshaped to cylindric, 10.6–43 × 6.3–11.1 mm, base tapering or rounded, not longitudinally ridged. Seeds: coat anticlinal cell-walls straight, papillae 4–11 per cell. 2n = 22.

Distribution

V12 538-distribution-map.jpg

B.C., Ariz., Calif., Idaho, Mont., Nev., Oreg., Utah, Wash., Wyo.

Discussion

Varieties 2 (2 in the flora).

Selected References

None.

Key

1 Petals 43–70 mm; 5 outermost stamens 39–55 mm. Mentzelia laevicaulis var. laevicaulis
1 Petals 23.5–40 mm; 5 outermost stamens 17.7–29 mm. Mentzelia laevicaulis var. parviflora
... more about "Mentzelia laevicaulis"
petaloid +  and heteromorphic +
elliptic +  and linear to narrowly +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
1.77 cm17.7 mm <br />0.0177 m <br /> (5.5 cm55 mm <br />0.055 m <br />) +
not clawed +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
John J. Schenk +  and Larry Hufford +
(Douglas) Torrey & A. Gray +
not +  and clasping +
ridged +, rounded +  and tapering +
Bartonia laevicaulis +
1.74 cm17.4 mm <br />0.0174 m <br /> (19.6 cm196 mm <br />0.196 m <br />) +
unlobed;lobed;orbiculate;obovate;unlobed;lobed;orbiculate;obovate;unlobed;lobed;orbiculate;obovate;oblanceolate;spatulate;linear;lanceolate;elliptic;ovate;cordate;deltate;hastate +
0.24 cm2.4 mm <br />0.0024 m <br /> (2.46 cm24.6 mm <br />0.0246 m <br />) +
widest;6.7mm;40.4mm +
upcurved +  and antrorse +
distal +  and along entire stem +
glabrescent +  and hairy +
1.06 cm10.6 mm <br />0.0106 m <br /> (4.3 cm43 mm <br />0.043 m <br />) +
cupshaped +  and cylindric +
0.63 cm6.3 mm <br />0.0063 m <br /> (1.11 cm11.1 mm <br />0.0111 m <br />) +
Giant blazingstar +
B.C. +, Ariz. +, Calif. +, Idaho +, Mont. +, Nev. +, Oreg. +, Utah +, Wash. +  and Wyo. +
curved +  and straight +
s--shaped +, clavate +, urceolate +, ovoid +, cylindric +, subcylindric +, lingulate +  and cup-shaped +
complex +  and simple +
free +  and adnate +
unlobed +  and filiform +
cauline +  and basal +
pinnate +  and entire +
apical +, subapical +  and inferior +
perpendicular +  and oriented +
not elongating +
inconspicuous +
connate +  and distinct +
2.35 cm23.5 mm <br />0.0235 m <br /> (7 cm70 mm <br />0.07 m <br />) +
spreading +  and erect +
hairy +  and glabrous +
Obovate (?) +, Oblanceolate (?) +, Elliptic (?) +, Ovate (?) +  and Spatulate (?) +
0.3 cm3 mm <br />0.003 m <br /> (1.73 cm17.3 mm <br />0.0173 m <br />) +
0 cm0 mm <br />0 m <br /> (1 cm10 mm <br />0.01 m <br />) +
Fl. N. Amer. +
flattened +  and ovoid +
persistent +
lanceolate +  and narrowly ovate +
Weedy +, Illustrated +  and Endemic +
golden yellow +
adnate +, free +  and distinct +
included +  and exserted +
straight +
papillate +
3-lobed +  and lingulate +
2.04 cm20.4 mm <br />0.0204 m <br /> (5.7 cm57 mm <br />0.057 m <br />) +
Mentzelia laevicaulis +
Mentzelia sect. Bartonia +
species +
dendritic +  and unbranched +
sinuous +  and straight +
perennial +  and biennial +
plant +  and bushlike +