Chaenactis artemisiifolia

(Harvey & A. Gray) A. Gray

Proc. Amer. Acad. Arts 10: 74. 1874.

Common names: White pincushion
Basionym: Acarphaea artemisiifolia Harvey & A. Gray Mem. Amer. Acad. Arts, n. s. 4: 98. 1849 (as artemisiaefolia)
Treatment appears in FNA Volume 21. Treatment on page 402. Mentioned on page 411.

Plants (15–) 25–90 (–200) cm. Leaves basal (withering) and cauline, 3–15 (–20) cm; largest blades ± plane, not succulent; primary lobes mostly 5–10 pairs, ultimate lobes ± crowded, antrorse, lanceolate to elliptic, plane. Peduncles 1.5–6 cm. Involucres ± hemispheric, mostly 10–15 mm diam. Phyllaries: longest 7–10 (–12) mm, ± densely villous, not or sparsely glandular; apices (all) erect, ± green, acute or scarcely acuminate, not aristate, ± plane. Receptacles: paleae 0. Corollas 5–7 mm. Cypselae compressed, 4–7 mm; pappi 0 or coroniform (of ± 10 scales, longest 0.1–0.5 mm). 2n = 16.


Phenology: Flowering Apr–early Jul.
Habitat: Dry canyons, open slopes, often over granitoid rocks, locally abundant in chaparral burns or other recovering disturbances
Elevation: 80–1600 m

Distribution

V21-1011-distribution-map.gif

Calif., Mexico (Baja California)

Discussion

In the flora area, Chaenactis artemisiifolia is known from the Transverse and Peninsular ranges and seaward valleys of southwestern California. It is fire-adapted; its germination is significantly enhanced by exposure to biomass smoke (J. E. Keeley and C. J. Fotheringham 1998).

Chaenactis lacera Greene, the eighteenth species of the genus, is known from coastal portions (including islands) of the western Vizcaíno Desert in Baja California and Baja California Sur, Mexico. Forms of C. artemisiifolia sometimes resemble C. lacera in coastal southern California (P. Stockwell 1940), where C. lacera could eventually be introduced. Besides the key characteristics above, C. lacera differs from C. artemisiifolia by its largest leaf blades broadly ± elliptic, 2–3-pinnately lobed, ultimate lobes remote, recurved to retrorse, ± linear, involute (leaf blades appearing ± skeletal).

Selected References

None.

Lower Taxa

None.

"longest" is not a number.

... more about "Chaenactis artemisiifolia"
not tailed +, rounded +  and obtuse +
connate +  and distinct +
subequal +
scarious +
usually ovate +  and lanceolate +
usually deltate +  and lanceolate +
paniculiform +, cymiform +  and corymbiform +
indeterminate +  and determinate +
James D. Morefield +
(Harvey & A. Gray) A. Gray +
decurrent +
Acarphaea artemisiifolia +
compound +  and simple +
lobed;ovate;oblanceolate;ovate;oblanceolate;linear;deltate +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
barbellulate +  and barbellate +
connate +  and distinct +
White pincushion +
actinomorphic +
white +  and pinkish +
stipitate-glandular +  and hairy +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
compressed +
fertile +  and bisexual +
fertile +  and bisexual +
Calif. +  and Mexico (Baja California) +
80–1600 m +
strigose +  and densely sericeous +
scabrellous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
campanulate +  and cylindric +
Dry canyons, open slopes, often over granitoid rocks, locally abundant in chaparral burns or other recovering disturbances +
in more or less cymiform arrays +, singly +  and radiant +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
hemispheric +
15 cm150 mm <br />0.15 m <br /> (20 cm200 mm <br />0.2 m <br />) +
cauline +  and basal +
3 cm30 mm <br />0.03 m <br /> (?) +  and 15 cm150 mm <br />0.15 m <br /> (?) +
deltate +  and more or less lanceolate +
dentate to pinnatifid or palmatifid +  and entire +
acute +  and acuminate-aristate +
2-carpellate +
persistent +
coroniform +
1.5 cm15 mm <br />0.015 m <br /> (6 cm60 mm <br />0.06 m <br />) +
Flowering Apr–early Jul. +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
5 +  and 21 +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
not arachnoid +  and farinose +
Proc. Amer. Acad. Arts +
bearing subulate enations +, hairy +  and bristly +
knobby;convex;more or less flat +
distinct +
4 +  and 20 +
exalbuminous +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Undefined (tribe Undefined) subtribe Bahiinae +  and Undefined (tribe Undefined) subtribe Palafoxiinae +
Chaenactis artemisiifolia +
Chaenactis sect. Acarphaea +
species +
cylindric +
80 cm800 mm <br />0.8 m <br /> (300 cm3,000 mm <br />3 m <br />) +
1 cm10 mm <br />0.01 m <br /> (80 cm800 mm <br />0.8 m <br />) +
plane;lanceolate;elliptic +
toothed +  and entire +
70 cm700 mm <br />0.7 m <br /> (200 cm2,000 mm <br />2 m <br />) +
5 cm50 mm <br />0.05 m <br /> (70 cm700 mm <br />0.7 m <br />) +