Ericameria
Trans. Amer. Philos. Soc., n. s. 7: 318. 1840.
Shrubs (trees in Ericameria parishii var. parishii), 10–500 cm. Stems usually erect to ascending, rarely prostrate, fastigiately or intricately branched (bark typically tan to reddish brown, becoming gray, twigs usually green to gray or yellowish), glabrous or sparsely to densely hairy (often tomentose), often gland-dotted, sometimes resinous or stipitate-glandular. Leaves (mostly persistent) cauline (often crowded, axillary leaf fascicles sometimes present); petiolate or sessile; blades (green to grayish; midnerves obscure to prominent, sometimes with 2 collateral veins), cuneate, elliptic, filiform, lanceolate, linear, oblanceolate, obovate, or spatulate (adaxially sulcate, concave, or flat), margins entire (sometimes undulate or crisped; apices acute to rounded or retuse), faces glabrous or sparsely to densely hairy (often tomentose), often stipitate-glandular, sometimes gland-dotted or resinous. Heads radiate or discoid, borne singly or in cymiform or racemiform, sometimes highly branched and paniculiform or thyrsiform, arrays. Involucres campanulate, cylindric, hemispheric, obconic, or turbinate, (4–19+ ×) 2–18 mm. Phyllaries 8–60 in 2–7 series (often in vertical ranks), 1-nerved (midnerves obscure or evident, sometimes enlarged subapically and glandular) ovate, lanceolate, or elliptic, strongly unequal to subequal, outer often herbaceous or herbaceous-tipped, otherwise mostly chartaceous, (apices erect, spreading, or reflexed, acute or acuminate to cuspidate or obtuse), faces sometimes stipitate-glandular, often resinous. Receptacles slightly convex, pitted, epaleate. Ray florets 0, or 1–18, pistillate, fertile; corollas usually yellow (white in E. gilmanii and E. resinosa), (laminae elliptic to oblong, apices shallowly notched or toothed). Disc florets 4–70, bisexual, fertile; corollas usually yellow (white in E. gilmanii and E. resinosa), tubes shorter than narrowly funnelform to campanulate throats, lobes 5, erect to spreading or reflexed, deltate to triangular; style-branch appendages lanceolate to subulate. Cypselae (tan to reddish brown) usually prismatic, sometimes cylindric, ellipsoid, obconic, or turbinate, 5–12-ribbed, faces glabrous or sparsely to densely hairy, sometimes gland-dotted; pappi persistent or tardily falling, of 20–60 whitish or tan to reddish, subequal, fine, barbellate, apically attenuate bristles in 1 series. x = 9.
Distribution
w North America, n Mexico.
Discussion
Species 36 (34 in the flora).
Two species, Ericameria juarezensis and E. martirensis, are known only from mountains in northern Baja California, Mexico. The plants inhabit rock outcrops and dry, stony or sandy substrates of western North America. Some taxa are widespread and codominant in scrub communities of that region; others have restricted distributions. Systematic and phylogenetic investigations have resulted in the expansion of Ericameria to include certain taxa previously assigned to Chrysothamnus as well as taxa treated in Haplopappus. Except for E. laricifolia, taxa in Texas previously included in Ericameria are but distantly related and have been excluded from the genus.
In the descriptions below, short-stipitate-glandular refers to hairs with stalks less than 1/2 as long as the diameter of the distal gland, long-stipitate-glandular to hairs with stalks clearly visible, 1–3-times longer than the diameter of the distal gland.
Selected References
Lower Taxa
Key
| 1 | Phyllaries usually subequal (outer more than 1/2 or equaling or longer than inner; sometimes unequal in E. resinosa), entirely herbaceous and leaflike or wholly chartaceous (sometimes each outer phyllary with an herbaceous or chartaceous appendage) | > 2 |
| 1 | Phyllaries unequal, chartaceous or outer wholly herbaceous or with herbaceous tips or subapical patches | > 15 |
| 2 | Ray florets usually 1–18, sometimes 0 (in E. greenei) | > 3 |
| 2 | Ray florets 0 | > 9 |
| 3 | Leaves gland-dotted (in circular, deep pits); heads borne singly; peduncles 20–70 mm (bracts usually 0); florets 23–78 | Ericameria linearifolia |
| 3 | Leaves resinous, gland-dotted (sessile), or stipitate-glandular; heads usually in cymiform or racemiform arrays, rarely borne singly; peduncles usually 0.3–20 mm (if longer, leafy-bracteate); florets usually 4–30 (15–40 in E. suffruticosa, a stipitate-glandular species) | > 4 |
| 4 | Stems and leaves stipitate-glandular | > 5 |
| 4 | Stems and leaves glabrous, tomentose, or gland-dotted (sessile or in pits) | > 7 |
| 5 | Phyllaries unequal (outer usually ca. 1/2 as long as involucres), outer herbaceous or herbaceous-appendaged, midnerves evident | Ericameria watsonii |
| 5 | Phyllaries subequal (outer mostly longer than and overtopping inner), herbaceous or herbaceous-appendaged, midnerves (plus 2, fainter, lateral nerves) often evident | > 6 |
| 6 | Heads in congested, cymiform or racemiform arrays; disc florets 7–20 | Ericameria greenei |
| 6 | Heads often borne singly or (2–3) in (leafy) racemiform arrays; disc florets 15–40 | Ericameria suffruticosa |
| 7 | Disc florets 10–15; corollas (white) 6–8 mm | Ericameria resinosa |
| 7 | Disc florets 4–14; corollas (yellow) 7–11 mm | > 8 |
| 8 | Ray laminae 6–12 mm; nw North America | Ericameria bloomeri |
| 8 | Ray laminae 3–4 mm; s Utah | Ericameria lignumviridis |
| 9 | Twigs resinous or stipitate-glandular (not tomentose, non-glandular hairs sometimes interspersed, never abundant) | > 10 |
| 9 | Twigs densely hairy (sometimes tomentose), eglandular | > 12 |
| 10 | Cypselae sparsely, evenly strigose (leaf margins crisped) | Ericameria crispa |
| 10 | Cypselae glabrous, glabrate, or apically sparsely hairy (leaf margins flat) | > 11 |
| 11 | Involucres 12–15 mm; disc corollas 9.1–11.5 mm (style branches 3.2–4.5 mm); s Nevada | Ericameria compacta |
| 11 | Involucres 14–22 mm; disc corollas 9.5–12 mm (style branches 4.2–5.2 mm); s Utah | Ericameria zionis |
| 12 | Leaves stipitate-glandular | > 13 |
| 12 | Leaves glabrous or whitish tomentose (not stipitate-glandular) | > 14 |
| 13 | Leaves 2–7 mm wide; Rocky Mountains | Ericameria discoidea |
| 13 | Leaves 1–2 mm wide; sw Montana, nw Wyoming | Ericameria linearis |
| 14 | Heads in congested, racemiform or cymiform clusters or paniculiform or thyrsiform arrays (heads sometimes 1–4 in E. parryi var. monocephala); leaves sometimes densely gray, greenish, or yellowish tomentose, not silvery white | Ericameria parryi |
| 14 | Heads borne singly or 2–3 in racemiform arrays; leaves densely, silvery white tomentose; Wyoming, adjacent Idaho (in E. parryi var. monocephala, single heads sometimes overtopped by leaves and phyllaries usually unequal; California, Nevada) | Ericameria winwardii |
| 15 | Leaves cuneate, elliptic, filiform, linear, oblanceolate, obovate, or spatulate (flat), 0.5–16 mm wide | > 16 |
| 15 | Leaves elliptic, filiform, linear, oblanceolate, narrowly obovate, or spatulate (terete or adaxially sulcate), usually 0.3–2(–4) mm wide | > 21 |
| 16 | Leaves cuneate, elliptic, obovate, or spatulate, apices usually obtuse, rounded, or retuse (sometimes acute in E. cervina) | > 17 |
| 16 | Leaves elliptic, filiform, linear, oblanceolate, or oblong, apices acute | > 19 |
| 17 | Leaves gland-dotted (in pits); ray florets usually 0 | Ericameria cuneata |
| 17 | Leaves stipitate-glandular or gland-dotted (sessile), resinous; ray florets usually 1–8, sometimes 0 | > 18 |
| 18 | Leaves 9–18 × 2.5–4 mm; ray florets 3–4; nw Arizona, adjacent Nevada, Utah | Ericameria cervina |
| 18 | Leaves 10–30 × 4–12 mm; ray florets 4–9; mainly c, n Utah | Ericameria obovata |
| 19 | Stems and leaves short-stipitate-glandular; leaves 10–35 mm; ray florets 1–8 (Grand Canyon, Arizona) | Ericameria arizonica |
| 19 | Stems and leaves gland-dotted (sessile) or tomentose; leaves 25–80 mm; ray florets 0 | > 20 |
| 20 | Disc florets 7–15; s California | Ericameria parishii |
| 20 | Disc florets (4–)5(–6); Utah | Ericameria nauseosa |
| 21 | Ray florets usually 0 (sometimes 1–2 in E. brachylepis) | > 22 |
| 21 | Ray florets usually 1–10 (sometimes 0 in E. cooperi) | > 28 |
| 22 | Phyllaries: midnerves mostly obscure, apices each bearing a subspheric resin-gland | Ericameria teretifolia |
| 22 | Phyllaries: midnerves usually raised and visible along entire length, apices sometimes with elongate, raised (never subspheric) glands | > 23 |
| 23 | Outer and mid phyllary apices often cuspidate (bodies apically truncate or narrowing abruptly to bases of herbaceous appendages), tips spreading to recurved (phyllary apices long-attenuate in some varieties of E. nauseosa, then erect, not recurved, and stems densely tomentose) | > 24 |
| 23 | Outer and mid phyllary apices acute to acuminate or rounded (bodies apically tapering), tips erect | > 25 |
| 24 | Involucres 6–10 mm; Great Basin region | Ericameria albida |
| 24 | Involucres 10–15 mm; n California | Ericameria ophitidis |
| 25 | Young stems usually densely tomentose; leaves gland-dotted or resinous and gland-dotted (not in circular pits); phyllaries often in vertical ranks; disc florets (4–)5(–6) | Ericameria nauseosa |
| 25 | Young stems usually glabrous, gland-dotted, resinous; leaves gland-dotted (in circular, deep pits); phyllaries usually in spirals (sometimes in ± vertical ranks in E. paniculata); disc florets usually 6–25 | > 26 |
| 26 | Young stems black-banded or splotched (from fungal infections); phyllary midnerves not or slightly raised; desert, California, Arizona, Nevada, sw Utah | Ericameria paniculata |
| 26 | Young stems without dark bands or splotches; phyllary midnerves raised and ± expanded distally; chaparral, California (E. brachylepis also disjunct in Arizona) | > 27 |
| 27 | Leaves 25–90 mm; heads in cymiform arrays, peduncles 1–15 mm (bracts 0–7, scalelike); florets 10–25 | Ericameria arborescens |
| 27 | Leaves 10–25 mm; heads in racemiform to paniculiform arrays,peduncles 3–20 mm (leafy or bracteate); florets 6–16(–22) | Ericameria brachylepis |
| 28 | Phyllary apices (outer and mid) cuspidate, appendages squarrose or recurved, herbaceous (bodies apically obtuse to retuse; disc corollas white) | > 29 |
| 28 | Phyllary apices acute to rounded or apiculate to cuspidate, appendages 0 or erect, sometimes herbaceous | > 30 |
| 29 | Leaves narrowly obovate (sometimes conduplicate), 2–4 mm wide; Inyo County, California | Ericameria gilmanii |
| 29 | Leaves filiform to narrowly oblanceolate, 0.5–1.5 mm wide; Idaho, Oregon, Washington | Ericameria resinosa |
| 30 | Leaves sometimes gland-dotted (in irregular, shallow pits), resinous; mid phyllary apices often aristate to cuspidate, appendages erect (bodies apically obtuse or truncate to retuse, midnerves not evident or slightly raised, slightly expanded subapically); desert mountains, e California, Idaho, Nevada, Oregon, Utah | Ericameria nana |
| 30 | Leaves gland-dotted (in circular, deep pits), often resinous; mid phyllary apices usually acute, obtuse, or rounded, if aristate to cuspidate, appendages erect (arising from acute, obtuse, or rounded body apices, midnerves raised and subapically expanded, usually each with conspicuous, subapical gland); Arizona, California, Nevada, New Mexico, w Texas, Utah | > 31 |
| 31 | Peduncles 5–15 mm (bracts 0–2); flowering spring | Ericameria cooperi |
| 31 | Peduncles 1–30 mm (if 5+ mm, leafy); flowering late summer–fall | > 32 |
| 32 | Axillary leaf fascicles sometimes present; desert mountains of California to Utah, w Texas, adjacent Mexico | Ericameria laricifolia |
| 32 | Axillary leaf fascicles usually present; California, Baja California (Mexico) | > 33 |
| 33 | Outermost phyllaries not herbaceous-appendaged (apices rounded, acute, or acuminate); cypselae usually sericeo-villous to densely hairy | > 34 |
| 33 | Outermost phyllaries herbaceous-appendaged; cypselae glabrous or hairy (more densely distally) | > 35 |
| 34 | Phyllaries yellowish tan, 0.6–1.5 mm wide (apices acute to acuminate or cuspidate, midnerves ± thickened); disc florets 18–25; c California (Monterey County) | Ericameria fasciculata |
| 34 | Phyllaries tan, 0.4–0.8 mm wide (apices usually rounded or obtuse, rarely acute, midnerves conspicuously thickened); disc florets 6–20; s California (Ventura County and south) | Ericameria palmeri |
| 35 | Leaves 3–18(–23) mm; ray florets 2–6; disc florets 5–14; dunes or sand hills along or near coast, Los Angeles to Sonoma counties, California | Ericameria ericoides |
| 35 | Leaves 12–35 mm; ray florets 3–10; disc florets 11–25; usually sandy to stony, often disturbed, soils away from coast, Ventura County, California (and south) | Ericameria pinifolia |