Baccharis pilularis |
Baccharis glomeruliflora |
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chaparral broom, coyote brush, dwarf chaparral false willow |
silverling |
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Habit | Shrubs, 15–450 cm (prostrate and mat-forming to erect and rounded, much branched). | Shrubs, 100–300 cm (evergreen, loosely branched). | ||||
Stems | spreading to ascending, dark brown, shiny, striate-angular, glabrous, often ± scurfy, usually resinous and sticky. |
erect to ascending, striate-angled, glabrous or minutely scurfy, not resinous. |
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Leaves | present at flowering; sessile or short-petiolate; blades (1- or 3-nerved) oblanceolate to obovate, the smaller 5–40 × 2–15 mm (thick), bases cuneate, margins entire or coarsely dentate (teeth 3–9 distal to middles), faces glabrous, gland-dotted, resinous. |
present at flowering (not in fascicles); petioles to 7 mm; blades obovate or elliptic to rhombic, 20–60 × 8–40 mm, leathery, bases cuneate to attenuate, margins serrate (teeth 1–3 per side distal to middles, relatively broad), apices acute, faces glabrous, abaxial black gland-dotted (distal reduced, entire), adaxial eglandular. |
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Involucres | hemispheric to campanulate; staminate 3.2–5 mm, pistillate 3–6 mm. |
campanulate to obconic; staminate 4–5 mm, pistillate 5–6 mm. |
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Pistillate florets | 19–43; corollas 2.5–3.5 mm. |
15–25; corollas 3–4 mm. |
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Staminate florets | 20–34, 3–4 mm. |
20–30; corollas 4–5 mm. |
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Phyllaries | ovate to lanceolate, 1–3 mm, margins yellowish, scarious, medians yellow proximally, green distally, apices obtuse to acute or acuminate (erose, abaxial faces papillose-scurfy). |
ovate to lanceolate, 1–4 mm, margins scarious, medians green, apices rounded or obtuse (sometimes purplish). |
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Heads | (100–200+) in (leafy) paniculiform arrays. |
(1–4, sessile or subsessile) in axillary glomerules scattered along branches. |
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Cypselae | 1–2 mm, 8–10-nerved, glabrous; pappi 6–9 mm. |
1.5–2 mm, 8–10-nerved, glabrous; pappi 8–9 mm. |
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Baccharis pilularis |
Baccharis glomeruliflora |
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Phenology | Flowering Oct–Nov. | |||||
Habitat | Hammocks, moist woods, pine woods, swamps, swales, stream banks, ditches of inner dunes | |||||
Elevation | 0–100 m (0–300 ft) | |||||
Distribution |
CA; NM; OR; nw Mexico
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AL; FL; GA; MS; NC; SC
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Discussion | Subspecies 2 (2 in the flora). Baccharis pilularis can be distinguished by its dark brown stems, and serrate, obovate to oblanceolate leaves. In addition, plants from some dunes of the California coast are prostrate, a growth form unique to this genus in our region. The common, weedy, widespread form is subsp. consanguinea, which is typically erect, with its larger leaves 15–40 mm. Subspecies pilularis is known only from exposed sandy dunes and bluffs along the central coast of California. Its growth habit is matlike, and its larger leaves are 5–15 mm. The prostrate habit of subsp. pilularis is strikingly different from the upright habit of subsp. consanguinea. C. B. Wolf (1935) demonstrated that in at least some populations, the distinction between prostrate and erect forms has a genetic basis. Transplants from the wild of the prostrate and erect forms retained their respective growth habits when grown together in a sheltered location and the morphology of seedlings reflected the habit of the parents. Wolf’s arguments for recognizing the forms as subspecies are further supported by the existence of prostrate cultivars in the horticultural trade. On the other hand, both erect and prostrate forms grow in proximity throughout the range of subsp. pilularis. In many areas the forms intergrade completely; in others they can be easily distinguished. Two subspecies are recognized here, notwithstanding difficulties in identifying habit from pressed specimens, or by observations of populations where both growth forms coexist. Further study is needed, perhaps utilizing molecular characters and detailed observations of native populations. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Found primarily on the Coastal Plain, Baccharis glomeruliflora is recognized by the evergreen leathery leaves with broad teeth, and the small axillary glomerules of heads. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 29. | FNA vol. 20, p. 27. | ||||
Parent taxa | ||||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | B. sessiliflora | |||||
Name authority | de Candolle: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 5: 407. (1836) | Persoon: Syn. Pl. 2: 423. (1807) | ||||
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