Baccharis sarothroides

A. Gray

Proc. Amer. Acad. Arts 17: 211. 1882.

Common names: Greasewood rosin-brush groundsel desertbroom
Illustrated
Treatment appears in FNA Volume 20. Treatment on page 33. Mentioned on page 25.

Shrubs, 100–400 cm (much branched, broomlike). Stems erect, striate, sharply angled, green distally, glabrous, resinous. Leaves cauline (proximal withered and/or sparse at flowering); sessile; blades (1-nerved) linear-lanceolate, 5–15 × 1–2 mm, reduced to scales distally, thick, bases narrowed, margins entire (often revolute), apices acute, faces glabrous, minutely gland-dotted, resinous. Heads borne singly (on nearly leafless branches) or (laterally on branchlets) in dense paniculiform arrays. Involucres cylindric to hemispheric; staminate 4–5.2 mm, pistillate 3–8 mm. Phyllaries ovate to lanceolate, 1–5 mm, margins yellowish, slightly scarious, medians green to yellow, apices rounded to acute (greenish, abaxial faces glabrous, resinous). Staminate florets 18–35; corollas 4.2–5 mm. Pistillate florets 19–31; corollas 2.5–3.5 mm. Cypselae 2–2.6 mm, finely 8–10-nerved, glabrous; pappi 7–12 mm. 2n = 18.


Phenology: Flowering Aug–Nov.
Habitat: Gravelly and sandy washes, roadsides, railroads, mesquite flats, chaparral
Elevation: 50–1500 m

Distribution

V20-28-distribution-map.gif

Ariz., Calif., N.Mex., Tex., Mexico (Baja California), Mexico (Baja California Sur), Mexico (Sinaloa), Mexico (Sonora)

Discussion

Baccharis sarothroides is recognized by its broomlike habit, narrow, sharply angular, nearly leafless, green stems, soon-withering proximal leaves, scalelike distal leaves, and heads often terminal on long branches. Specimens from California have smaller heads that sometimes are arranged laterally along the stems.

Selected References

None.

Lower Taxa

None.
... more about "Baccharis sarothroides"
not tailed +, rounded +  and obtuse +
distinct +
subequal +
scarious +
usually triangular +  and linear +
usually deltate +  and lanceolate +
paniculiform +
indeterminate +  and determinate +
Scott D. Sundberg† +  and David J. Bogler +
A. Gray +
narrowed +
3-nerved +  and 1-nerved +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
linear-lanceolate +
reduced +
1mm;2mm +
rugulose +  and muricate +
barbellulate +  and barbellate +
Greasewood +, rosin-brush +, groundsel +  and desertbroom +
not 2-lipped +  and actinomorphic +
whitish +, white +  and pale-yellow +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
beaked +, 2-ribbed +  and 5-ribbed +
compressed +, obovoid +  and cylindric +
fertile +  and bisexual +
Ariz. +, Calif. +, N.Mex. +, Tex. +, Mexico (Baja California) +, Mexico (Baja California Sur) +, Mexico (Sinaloa) +  and Mexico (Sonora) +
50–1500 m +
resinous +
gland-dotted +
pistillate +  and staminate +
winged +  and beaked +
dispersed +
Gravelly and sandy washes, roadsides, railroads, mesquite flats, chaparral +
racemiform +, corymbiform +  and paniculiform +
in dense paniculiform arrays +  and singly +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
pistillate +  and staminate +
0.3 cm3 mm <br />0.003 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
cylindric;hemispheric +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
spreading-reflexed;spreading-reflexed +
less deltate +  and lanceovate +
hispid +  and glabrous +
green +  and yellow +
2-carpellate +
brownish +, whitish +  and tawny +
persistent +
25 +  and 50 +
0.7 cm7 mm <br />0.007 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
Flowering Aug–Nov. +
ovate +  and lanceolate +
0.1 cm1 mm <br />0.001 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Proc. Amer. Acad. Arts +
styliferous +, neuter +  and pistillate +
bearing subulate enations +, hairy +  and bristly +
conic;tholiform;conic;tholiform;flat +
exalbuminous +
Illustrated +
1 (?) +  and 20 (?) +
resinous +
appendaged +  and truncate +
papillate +  and smooth +
Compositae +
Baccharis sarothroides +
Baccharis +
species +