Baccharis havardii

A. Gray in A. Gray et al.

in A. Gray et al., Syn. Fl. N. Amer. 1(2): 224. 1884.

Common names: Havard’s false willow
Treatment appears in FNA Volume 20. Treatment on page 28. Mentioned on page 25.

Subshrubs, 15–70 cm (much branched from bases). Stems erect (green to tan), slender, striate-angled, glabrous, resinous. Leaves present at flowering; short-petiolate; blades (1-nerved) narrowly spatulate to linear, 20–40 × 2–3 mm, reduced to bracts distally, bases attenuate, margins entire or toothed (teeth to 2 mm), faces glabrous, gland-dotted, resinous. Heads in broad paniculiform arrays. Involucres cylindro-campanulate; staminate 3 mm, pistillate 4–4.5 mm. Phyllaries lanceolate, 1–4 mm, margins scarious, medians green or brownish, apices obtuse to acuminate (thickened, slightly erose and ciliate). Staminate florets 12–15; corollas 3–4 mm. Pistillate florets 15–20; corollas 3 mm. Cypselae 2–2.5 mm, 5-nerved, glabrous; pappi 4 mm.


Phenology: Flowering Jul–Sep.
Habitat: Dry rocky hillsides, open ground, calcareous gravels
Elevation: 1500–2300 m

Distribution

V20-16-distribution-map.gif

N.Mex., Tex., Mexico (Chihuahua)

Discussion

Found mainly in the Chisos and Davis Mountains of West Texas, Baccharis havardii is distinguished by its short bushy habit, narrow leaves with elongate teeth, and 5-nerved cypselae. G. L. Nesom (pers. comm.) suggested that it is weakly defined and further investigation may demonstrate it should be included in the Mexican species B. sulcata de Candolle (which name would have priority over B. havardii).

Selected References

None.

Lower Taxa

None.
... more about "Baccharis havardii"
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 in A. Gray et al. +
attenuate +
3-nerved +  and 1-nerved +
2 cm20 mm <br />0.02 m <br /> (4 cm40 mm <br />0.04 m <br />) +
narrowly spatulate;linear +
reduced +
2mm;3mm +
rugulose +  and muricate +
barbellulate +  and barbellate +
Havard’s false willow +
not 2-lipped +  and actinomorphic +
whitish +, white +  and pale-yellow +
3 cm30 mm <br />0.03 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
beaked +, 2-ribbed +  and 5-ribbed +
compressed +, obovoid +  and cylindric +
fertile +  and bisexual +
N.Mex. +, Tex. +  and Mexico (Chihuahua) +
1500–2300 m +
resinous +
gland-dotted +
pistillate +  and staminate +
winged +  and beaked +
dispersed +
Dry rocky hillsides, open ground, calcareous gravels +
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 />) +
cylindro-campanulate +
0.4 cm4 mm <br />0.004 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
short-petiolate +
spreading-reflexed;spreading-reflexed +
less deltate +  and lanceovate +
serrate +  and entire +
hispid +  and glabrous +
toothed +  and entire +
brownish +  and green +
2-carpellate +
brownish +, whitish +  and tawny +
persistent +
25 +  and 50 +
4 cm40 mm <br />0.04 m <br /> (?) +
Flowering Jul–Sep. +
lanceolate +
0.1 cm1 mm <br />0.001 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
in A. Gray et al., Syn. Fl. N. Amer. +
styliferous +, neuter +  and pistillate +
bearing subulate enations +, hairy +  and bristly +
conic;tholiform;conic;tholiform;flat +
exalbuminous +
1 (?) +  and 20 (?) +
resinous +
striate-angled +
slender +
appendaged +  and truncate +
papillate +  and smooth +
Compositae +
Baccharis havardii +
Baccharis +
species +