Boechera yorkii

S. Boyd

Madroño 51: 387, figs. 1–3. 2004.

Treatment appears in FNA Volume 7. Treatment on page 412. Mentioned on page 351.

Perennials; long-lived; sexual; caudex woody. Stems usually 1 per caudex branch, arising from center of rosette near ground surface, 1–3 dm, densely pubescent proximally, trichomes short-stalked, 4–7-rayed, 0.1–0.5 mm, mixed proximally with simple and short to long-stalked, 2-rayed or 3-rayed ones, to 1.5 mm, moderately pubescent distally. Basal leaves: blade linear-oblanceolate, 1.5–3 mm wide, margins entire, ciliate proximally, trichomes (simple and 2-rayed or 3-rayed), to 1.5 mm, surfaces moderately pubescent, trichomes short-stalked, 4–7-rayed, 0.3–0.6 mm. Cauline leaves: 9–17, concealing stem proximally; blade auricles absent, surfaces of distalmost leaves moderately pubescent. Racemes 8–35-flowered, usually unbranched. Fruiting pedicels reflexed, straight, 1.5–2 mm, pubescent, trichomes appressed, branched. Flowers pendent at anthesis; sepals pubescent; petals yellowish proximally and brick-red distally or, rarely, one color throughout, 9–10 × 0.8–1 mm, glabrous; pollen ellipsoid. Fruits (immature) reflexed, often appressed to rachis, not secund, straight, edges parallel, ca. 4 cm; valves pubescent throughout; style ca. 0.3 mm. Seeds not seen.


Phenology: Flowering May.
Habitat: Crevices and ledges of calcareous rock outcrops
Elevation: 2200-2400 m

Discussion

Boechera yorkii is immediately recognizable by its yellowish to brick-red petals and extremely short (1.5–2 mm), reflexed fruiting pedicels. It is known only from Last Chance Mountains in Inyo County.

Selected References

None.

Lower Taxa

None.

"elongated" is not a number."thick" is not a number."dm" is not declared as a valid unit of measurement for this property.

... more about "Boechera yorkii"
oblong +  and ovate +
Ihsan A. Al-Shehbaz +  and Michael D. Windham +
S. Boyd +
not +  and rosulate +
appendaged +  and unappendaged +
lyrate-pinnatifid +, dentate +  and entire +
dissected +, repand +, sinuate +, crenate +  and dentate +
linear-oblanceolate +
much smaller +  and reduced +
1.5mm;3mm +
urceolate +, campanulate +  and tubular +
branched +  and simple +
petiolate +  and sessile +
well-developed +
indistinct +
not +  and differentiated +
emarginate +  and entire +
2200-2400 m +
straight +  and curved +
not winged +  and unappendaged +
connate +  and distinct +
actinomorphic +
straight +
torulose +, falcate +, lanceolate +, oblong +  and linear +
Crevices and ledges of calcareous rock outcrops +
annular +  and semiannular +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
pinnatifid +
prominent +  and obscure +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
0.9 cm9 mm <br />0.009 m <br /> (1 cm10 mm <br />0.01 m <br />) +
rudimentary +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Flowering May. +
trinucleate +  and 3(-11)-colpate +
ellipsoid +
unbranched;8-35-flowered +
elongated +
reflexed +, ascending +  and erect +
slender +
mucilaginous +
margined +, not winged +  and winged +
biseriate +, sub-biseriate +  and uniseriate +
not +  and mucilaginous +
White (?) +, Black (?) +, Brown (?) +  and Yellow (?) +
orbicular +, oblong +  and flattened +
persistent +  and caducous +
distinct +
spreading +, ascending +  and erect +
oblong +  and ovate +
reduced +
latiseptate +, schizocarpic +, samaroid +  and lomentaceous +
indehiscent +  and dehiscent +
angustiseptate +, flat +, angled +, terete +, torulose +, not +, segmented +  and nutletlike +
tetradynamous +
branched +  and unbranched +
procumbent +  and decumbent +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0.3 cm3 mm <br />0.003 m <br /> (?) +
Cruciferae +
Boechera yorkii +
Boechera +
species +
branched +, short-stalked +  and long-stalked +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
coiled +, 1-7-veined +  and veined +
anastomosing +
perennial +  and long-lived +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +