Erigeron vreelandii |
Erigeron tracyi |
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sticky tall fleabane, Vreeland's erigeron |
running fleabane |
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Habit | Perennials 30–80 cm; rhizomatous to subrhizomatous, fibrous-rooted, caudices usually relatively short and few branched, thick, woody. | Annuals, biennials, or short-lived perennials, 2.5–8(–12, 18) cm; usually taprooted, sometimes fibrous-rooted, caudices simple or branched. |
Stems | erect, sometimes sparsely pilose (hairs 1–2 mm), densely stipitate-glandular. |
first erect (greenish proximally), then producing herbaceous, leafy, prostrate runners (stoloniform branches, sometimes with rooting plantlets at tips), densely hirsutulous (hairs spreading-deflexed, of relatively even lengths and orientations), sparsely minutely glandular. |
Leaves | basal (usually withering by flowering) and cauline; basal blades oblanceolate-spatulate, 30–80 × 5–20(–25) mm (bases usually clasping to subclasping), margins entire, faces glabrous, densely stipitate-glandular; cauline blades narrowly lanceolate to oblong-, ovate-, or elliptic-lanceolate, nearly even-sized distally or sometimes mid largest (continuing to immediately proximal to heads). |
mostly basal (persistent in early season); blades oblanceolate to spatulate (obovate-elliptic laminae), 10–30(–60) × 3–6(–12) mm, cauline abruptly reduced distally, margins entire, dentate, or lobed, faces densely hirsute, eglandular. |
Involucres | 6–9 × 10–15(–18) mm. |
3.5–4.5(–6) × 6–9(–12) mm. |
Ray florets | 75–150; corollas blue to lavender, 9–17 mm (ca. 1 mm wide), laminae coiling. |
60–130; corollas white, often purplish abaxially, sometimes with an abaxial midstripe, 5–9 mm, laminae not coiling or reflexing. |
Disc corollas | 3–4 mm. |
2–3 mm (throats indurate and slightly inflated). |
Phyllaries | in 2–3(–4) series, densely stipitate-glandular. |
in 3–4 series, sparsely to moderately hirsute, minutely glandular. |
Heads | 1–15(–22) in corymbiform arrays. |
1(–3 rarely, from midstem or proximal branches). |
Cypselae | 1.7–2 mm, 2-nerved, faces sparsely strigose; pappi: outer of (conspicuous) scales, inner of 14–22 bristles. |
0.7–1.3 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 12–16 bristles. |
2n | = 18. |
= 27. |
Erigeron vreelandii |
Erigeron tracyi |
|
Phenology | Flowering Jul–Sep(–Oct). | Flowering Mar–Oct. |
Habitat | Openings and open woods, oak-pine, ponderosa pine, pine-fir | Desert scrub, grassy slopes, oak chaparral, pinyon-juniper woodlands, Douglas fir-ponderosa pine |
Elevation | (1300–)1800–3100 m ((4300–)5900–10200 ft) | 700–2300(–2400) m (2300–7500(–7900) ft) |
Distribution |
AZ; CO; NM; Mexico (Sonora)
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AZ; CO; KS; NM; NV; OK; TX; UT; Mexico (Baja California, Chihuahua, Coahuila, Durango, Sonora, Zacatecas)
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Discussion | Erigeron vreelandii is similar to E. speciosus in its perennial duration, tall stature, subclasping, spreading leaves nearly even-sized up the stems, corymbiform arrays, and blue rays; it is distinguished by the prominent vestiture of relatively long stipitate-glandular hairs. Intermediates apparently are formed between the two. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
In March through June, plants of Erigeron tracyi produce leaves in a basal rosette usually with a single, erect, monocephalous, stem. Stoloniform branches are soon formed (often recognized on pressed specimens by the leaves mostly on one side of the branches), and by the end of the season (August through October), prostrate runners are usually evident, sometimes forming terminal, rooting plantlets. Erigeron tracyi is similar in habit to E. flagellaris, particularly in the herbaceous stolons or stoloniform branches; the stem pubescence of E. tracyi is different, the stolons much less commonly produce rooting plantlets at the tips, and the plants tend to be perennial with woody or lignescent caudices, although they are variable both in habit and duration. Apparent hybrids with E. modestus and E. flagellaris are occasionally encountered, and the most common form of E. tracyi is perhaps (speculative) a stabilized, apomictic hybrid between the latter and E. divergens. All chromosome counts thus far have shown E. tracyi to be triploid and asynaptic. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 331. | FNA vol. 20, p. 340. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | E. patens, E. platyphyllus, E. rudis | E. cinereus, E. colomexicanus, E. commixtus, E. divergens var. cinereus |
Name authority | Greene: Bull. Torrey Bot. Club 32: 125. (1905) | Greene: Pittonia 5: 59. (1902) |
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