Boechera cascadensis

Windham & Al-Shehbaz

Harvard Pap. Bot. 11: 260. 2007.

Basionym: Arabis microphylla var. thompsonii Rollins Rhodora 43: 429. 1941,
Treatment appears in FNA Volume 7. Treatment on page 369. Mentioned on page 364, 370, 390.

Perennials; long-lived; (cespitose); apomictic; caudex somewhat woody. Stems usually 1 per caudex branch, arising from center of rosette near ground surface, 0.5–2.2 dm, sparsely pubescent proximally, trichomes simple and short-stalked, 2-rayed or 3-rayed, 0.1–0.2 mm, glabrous distally. Basal leaves: blade linear-oblanceolate, 0.7–2 mm wide, margins entire, ciliate proximally, trichomes to 0.4 mm, surfaces densely pubescent, trichomes short-stalked, (2-rayed or) 3–6-rayed, 0.05–0.2 (–0.3) mm. Cauline leaves: 4–6, not concealing stem; blade auricles 0.5–1 mm, surfaces of distalmost leaves glabrous. Racemes 3–11-flowered, unbranched. Fruiting pedicels ascending to divaricate-ascending, straight, 3–8 mm, glabrous. Flowers ascending at anthesis; sepals glabrous or sparsely pubescent; petals lavender, 5–6 × 1–1.7 mm, glabrous; pollen spheroid. Fruits ascending to divaricate-ascending, not appressed to rachis, not secund, straight, edges parallel, 3.5–6.2 cm × 1.2–1.5 mm; valves glabrous; ovules 58–80 per ovary; style 0.8–1.5 mm. Seeds uniseriate, 1.1–1.3 × 0.9–1 mm; wing continuous, 0.05–0.1 mm wide.


Phenology: Flowering Jun.
Habitat: Basaltic cliffs and rocky slopes in subalpine areas
Elevation: ca. 1900 m

Discussion

Of conservation concern.

Morphological evidence suggests that Boechera cascadensis is an apomictic species that arose through hybridization between B. microphylla and B. paupercula (see M. D. Windham and I. A. Al-Shehbaz 2007 for detailed comparison). It is known from two collections: the type specimens from Kittitas County, Washington, and a more recent collection from Baker County, Oregon.

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 cascadensis"
oblong +  and ovate +
Ihsan A. Al-Shehbaz +  and Michael D. Windham +
Windham & Al-Shehbaz +
not +  and rosulate +
Arabis microphylla var. thompsonii +
appendaged +  and unappendaged +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
lyrate-pinnatifid +, dentate +  and entire +
dissected +, repand +, sinuate +, crenate +  and dentate +
linear-oblanceolate +
much smaller +  and reduced +
0.7mm;2mm +
urceolate +, campanulate +  and tubular +
branched +  and simple +
petiolate +  and sessile +
well-developed +
indistinct +
not +  and differentiated +
emarginate +  and entire +
Oreg. +  and Wash. +
3.5 cm35 mm <br />0.035 m <br /> (6.2 cm62 mm <br />0.062 m <br />) +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
ca. 1900 m +
straight +  and curved +
not winged +  and unappendaged +
connate +  and distinct +
actinomorphic +
straight +
ascending +  and divaricate-ascending +
torulose +, falcate +, lanceolate +, oblong +  and linear +
Basaltic cliffs and rocky slopes in subalpine areas +
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 +
Magenta (?) +, Red (?) +, Yellowish (?) +, Purple (?) +, Lavender (?) +, Pink (?) +  and White (?) +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
rudimentary +
0.1 cm1 mm <br />0.001 m <br /> (0.17 cm1.7 mm <br />0.0017 m <br />) +
Flowering Jun. +
trinucleate +  and 3(-11)-colpate +
spheroid +
Harvard Pap. Bot. +
unbranched;3-11-flowered +
elongated +
ascending +  and divaricate-ascending +
slender +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
mucilaginous +
margined +, not winged +  and winged +
biseriate +, sub-biseriate +  and uniseriate +
not +  and mucilaginous +
White (?) +, Black (?) +, Brown (?) +  and Yellow (?) +
0.11 cm1.1 mm <br />0.0011 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
orbicular +, oblong +  and flattened +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
persistent +  and caducous +
distinct +
spreading +, ascending +  and erect +
pubescent +  and glabrous +
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 +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
glabrous +  and pubescent +
Cruciferae +
Boechera cascadensis +
Boechera +
species +
short-stalked +  and simple +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
0.005 cm0.05 mm <br />5.0e-5 m <br /> (0.02 cm0.2 mm <br />2.0e-4 m <br />) +
coiled +, 1-7-veined +  and veined +
anastomosing +
perennial +  and long-lived +
hispid +, hirsute +, pubescent +  and glabrous +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +
0.05mm;0.1mm +