Alyssum desertorum

Stapf

Denkschr. Kaiserl. Akad. Wiss., Wien. Math.-Naturwiss. Kl. 51: 302. 1886.

WeedyIntroduced
Treatment appears in FNA Volume 7. Treatment on page 248.

Annuals; canescent throughout except fruit, trichomes appressed, 8–20-rayed. Stems simple or few to several from base, erect, ascending, or decumbent, (0.2–) 0.5–1.8 (–2.8) dm. Cauline leaves subsessile or (proximal) attenuate to petiolelike base (to 0.5 cm); blade linear to oblanceolate-linear, (0.3–) 0.5–2.5 (–3) cm × (0.5–) 1–3 (–4) mm (gradually smaller distally), base attenuate, apex acute. Fruiting pedicels ascending or subdivaricate, straight, stout, (1–) 1.5–3.5 (–4.5) mm, trichomes uniformly stellate. Flowers: sepals oblong, 1.4–1.8 (–2) × 0.4–0.5 mm, stellate-pubescent; petals pale-yellow, oblanceolate, 2–2.5 × 0.5–0.6 mm, base attenuate, apex obtuse or retuse, sparsely stellate-pubescent abaxially; filaments: median pairs not toothed, gradually expanded from apex to narrowly winged base, lateral pair with broadly winged appendage apically notched into 2 teeth, 1–1.8 (–2) mm; anthers ovate, 0.1–0.2 mm. Fruits orbicular, 2.5–4 (–4.5) mm diam., apex shallowly emarginate, usually glabrous; valves uniformly inflated at middle, broadly flattened at margins, often glaucous, rarely sparsely pubescent (when young); ovules 2 per ovary; style 0.3–0.7 mm, glabrous. Seeds ovoid, slightly compressed, 1.2–1.5 × 0.9–1.1 mm, margined or not. 2n = 32.


Phenology: Flowering Apr–Jul.
Habitat: Deserts, rocky areas, disturbed sites, roadsides, fields, meadows, sagebrush flats
Elevation: 800-2000 m

Distribution

V7 320-distribution-map.gif

Introduced; Alta., B.C., Sask., Calif., Colo., Idaho, Mont., Nebr., Nev., N.Dak., Oreg., S.Dak., Utah, Wash., Wyo., Europe, c Asia

Discussion

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 "Alyssum desertorum"
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.02 cm0.2 mm <br />2.0e-4 m <br />) +
glabrous +  and stellate-pubescent +
Retuse (?) +, Obtuse (?) +  and Acute (?) +
Ihsan A. Al-Shehbaz +
sessile +  and petiolate +
not +  and rosulate +
attenuate +
appendaged +  and unappendaged +
linear to oblanceolate-linear +
2.5 cm25 mm <br />0.025 m <br /> (3 cm30 mm <br />0.03 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
dissected +, repand +, sinuate +, crenate +  and dentate +
much smaller +  and reduced +
1mm;3mm +
urceolate +, campanulate +  and tubular +
branched +  and simple +
attenuate to petiolelike +  and subsessile +
well-developed +
distinct +
not +  and differentiated +
emarginate +  and entire +
incumbent +  and accumbent +
Alta. +, B.C. +, Sask. +, Calif. +, Colo. +, Idaho +, Mont. +, Nebr. +, Nev. +, N.Dak. +, Oreg. +, S.Dak. +, Utah +, Wash. +, Wyo. +, Europe +  and c Asia +
800-2000 m +
straight +  and curved +
appendaged +, winged +  and not winged +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
connate +  and distinct +
lateral +  and median +
not toothed +
0.1 cm1 mm <br />0.001 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
actinomorphic +
latiseptate +  and sessile +
orbicular +
latiseptate +  and unsegmented +
Deserts, rocky areas, disturbed sites, roadsides, fields, meadows, sagebrush flats +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
pinnatifid +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
rudimentary +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
Flowering Apr–Jul. +
trinucleate +  and 3(-11)-colpate +
Denkschr. Kaiserl. Akad. Wiss., Wien. Math.-Naturwiss. Kl. +
elongated +
reflexed +  and ascending +
stout +  and slender +
not +  and branched +
not +  and mucilaginous +
not +  and margined +
aseriate +  and biseriate +
not +  and mucilaginous +
White (?) +, Black (?) +, Brown (?) +  and Yellow (?) +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
compressed +  and ovoid +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
persistent +  and caducous +
distinct +
erect +  and spreading +
stellate-pubescent +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
reduced +
latiseptate +, schizocarpic +, samaroid +  and lomentaceous +
indehiscent +  and dehiscent +
angustiseptate +, flat +, angled +, terete +, torulose +, not +, segmented +  and nutletlike +
Weedy +  and Introduced +
tetradynamous +
few to several +  and simple +
procumbent +  and decumbent +
decumbent +, ascending +  and erect +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
Cruciferae +
Alyssum desertorum +
species +
simple +  and sessile +
pubescent +  and glaucous +
flattened +  and inflated +
anastomosing +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +