Boechera rectissima

(Greene) Al-Shehbaz

Novon 13: 388. 2003.

Basionym: Arabis rectissima Greene Pittonia 4: 191. 1900
Synonyms: Arabis setigera Greene Arabis wyndii L. F. Henderson
Treatment appears in FNA Volume 7. Treatment on page 401. Mentioned on page 350, 355, 356, 397, 410.

Biennials or perennials; short-lived; sexual; caudex present or absent. Stems usually 1 per caudex branch, arising from center of rosette near ground surface, 2–8 (–10) dm, usually glabrous proximally, rarely sparsely pubescent, trichomes simple, to 0.7 mm, glabrous distally. Basal leaves: blade oblanceolate, 3–8 (–13) mm wide, margins entire or denticulate, ciliate, trichomes (simple), 0.5–1.2 mm, surfaces sparsely to densely pubescent, trichomes simple, to 0.8 mm, often mixed with short-stalked, 2-rayed or 3-rayed ones, 0.15–0.5 mm. Cauline leaves: 6–30 (–45), often concealing stem proximally; blade auricles 1–1.5 mm, surfaces of distalmost leaves sparsely pubescent, sometimes margins ciliate. Racemes 10–30 (–50) -flowered, usually unbranched. Fruiting pedicels reflexed, abruptly recurved at base, otherwise straight, 4–10 mm, glabrous. Flowers pendent at anthesis; sepals pubescent; petals white, 3–4 × 0.7–1.2 mm, glabrous; pollen ellipsoid. Fruits strongly reflexed, usually appressed to rachis, not secund, straight, edges parallel, 5–9 cm × 1.8–2.5 mm; valves glabrous; ovules 46–80 per ovary; style 0.2–0.8 mm. Seeds uniseriate, 1.8–2.1 × 1–1.5 mm; wing continuous, 0.15–0.25 mm wide.


Phenology: Flowering May–Jul.
Habitat: Rocky slopes in open conifer forests
Elevation: 1500-2500 m

Discussion

Boechera rectissima is easily recognized by its combination of glabrous stems, basal leaves with large, predominantly simple trichomes, short (3–4 mm), white petals, and strongly reflexed, appressed fruits. Plants assigned to var. simulans appear to be hybrids between this species and B. retrofracta.

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

... more about "Boechera rectissima"
oblong +  and ovate +
Ihsan A. Al-Shehbaz +  and Michael D. Windham +
(Greene) Al-Shehbaz +
not +  and rosulate +
straight +
recurved +  and reflexed +
0.4 cm4 mm <br />0.004 m <br /> (1 cm10 mm <br />0.01 m <br />) +
Arabis rectissima +
appendaged +  and unappendaged +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
not +  and auriculate +
lyrate-pinnatifid +, dentate +  and entire +
dissected +, repand +, sinuate +, crenate +  and dentate +
oblanceolate +
much smaller +  and reduced +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
urceolate +, campanulate +  and tubular +
branched +  and simple +
petiolate +  and sessile +
well-developed +
indistinct +
not +  and differentiated +
emarginate +  and entire +
Calif. +  and Oreg. +
5 cm50 mm <br />0.05 m <br /> (9 cm90 mm <br />0.09 m <br />) +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
1500-2500 m +
straight +  and curved +
not winged +  and unappendaged +
connate +  and distinct +
actinomorphic +
straight +
torulose +, falcate +, lanceolate +, oblong +  and linear +
Rocky slopes in open conifer forests +
annular +  and semiannular +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
dentate +  and entire +
denticulate;entire +
prominent +  and obscure +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
rudimentary +
oblanceolate +  and spatulate +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
Flowering May–Jul. +
trinucleate +  and 3(-11)-colpate +
ellipsoid +
unbranched;10-30(-50)-flowered +
reflexed +, ascending +  and erect +
slender +
mucilaginous +
margined +, not winged +  and winged +
biseriate +, sub-biseriate +  and uniseriate +
not +  and mucilaginous +
white +, black +, brown +  and yellow +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.21 cm2.1 mm <br />0.0021 m <br />) +
orbicular +, oblong +  and flattened +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
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 +
pubescent +  and glabrous +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
Arabis setigera +  and Arabis wyndii +
Boechera rectissima +
Boechera +
species +
0.015 cm0.15 mm <br />1.5e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
coiled +, 1-7-veined +  and veined +
anastomosing +
perennial +, short-lived +  and biennial +
hispid +, hirsute +, pubescent +  and glabrous +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +
0.15mm;0.25mm +