Baccharis bigelovii

A. Gray in W. H. Emory

in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 84. 1859.

Common names: Bigelow’s false willow
Treatment appears in FNA Volume 20. Treatment on page 26. Mentioned on page 24, 25, 34.

Shrubs, 30–100 cm (branched from bases). Stems erect to ascending, slender, striate-angled, glabrous, resinous. Leaves present at flowering; short-petiolate; blades (1-nerved or obscurely 3-nerved) obovate to oblanceolate, 20–35 × 3–15 mm, distally reduced and narrowed, bases cuneate, margins irregularly incised to coarsely serrate or 2-serrate, faces glabrous, gland-dotted, resinous. Heads (20–50) in corymbiform arrays. Involucres campanulate; staminate 4–5 mm, pistillate 4–5 mm. Phyllaries lanceolate, 1–4 mm, margins scarious, medians green, apices acute, erose. Staminate florets 15–20; corollas 3.5–4 mm. Pistillate florets 25–30; corollas 2–2.6 mm. Cypselae 1.5–2.2 mm, 5-nerved, glabrous; pappi 3–4.5 mm.


Phenology: Flowering Aug–Nov.
Habitat: Dry rocky ground in coniferous forests
Elevation: 1300–2000 m

Distribution

V20-10-distribution-map.gif

Ariz., N.Mex., Tex., Mexico (Chihuahua), Mexico (Durango), Mexico (Sonora)

Discussion

Baccharis bigelovii occurs in the general Chihuahuan Desert region in the Davis Mountains of West Texas, and in the Chiricahua and Huachuca mountains of Arizona. It is recognized by the relatively short stature, obovate, coarsely and irregularly serrate leaves, erose-ciliate phyllaries, and 5-nerved cypselae. It is similar to B. thesioides, which differs mainly by having narrower, more oblong leaves with more evenly serrate margins and spinulose teeth. Further investigation may show these two taxa to be different geographic expressions of a single species centered in Mexico.

Selected References

None.

Lower Taxa

None.
... more about "Baccharis bigelovii"
not tailed +, rounded +  and obtuse +
distinct +
subequal +
scarious +
usually triangular +  and linear +
usually deltate +  and lanceolate +
indeterminate +  and determinate +
Scott D. Sundberg† +  and David J. Bogler +
A. Gray in W. H. Emory +
cuneate +
3-nerved +  and 1-nerved +
2 cm20 mm <br />0.02 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
narrowed;obovate;oblanceolate +
reduced +
3mm;15mm +
rugulose +  and muricate +
barbellulate +  and barbellate +
Bigelow’s false willow +
not 2-lipped +  and actinomorphic +
whitish +, white +  and pale-yellow +
0.2 cm2 mm <br />0.002 m <br /> (0.26 cm2.6 mm <br />0.0026 m <br />) +
beaked +, 2-ribbed +  and 5-ribbed +
compressed +, obovoid +  and cylindric +
fertile +  and bisexual +
Ariz. +, N.Mex. +, Tex. +, Mexico (Chihuahua) +, Mexico (Durango) +  and Mexico (Sonora) +
1300–2000 m +
resinous +
gland-dotted +
pistillate +  and staminate +
winged +  and beaked +
dispersed +
Dry rocky ground in coniferous forests +
racemiform +, corymbiform +  and paniculiform +
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 />) +
campanulate +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
short-petiolate +
spreading-reflexed;spreading-reflexed +
less deltate +  and lanceovate +
2-serrate +  and serrate +
hispid +  and glabrous +
2-carpellate +
brownish +, whitish +  and tawny +
persistent +
25 +  and 50 +
0.3 cm3 mm <br />0.003 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
Flowering Aug–Nov. +
lanceolate +
0.1 cm1 mm <br />0.001 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
in W. H. Emory, Rep. U.S. Mex. Bound. +
styliferous +, neuter +  and pistillate +
bearing subulate enations +, hairy +  and bristly +
conic;tholiform;conic;tholiform;flat +
exalbuminous +
1 (?) +  and 20 (?) +
resinous +
erect +  and ascending +
striate-angled +
slender +
appendaged +  and truncate +
papillate +  and smooth +
Compositae +
Baccharis bigelovii +
Baccharis +
species +