Gamochaeta purpurea |
Gamochaeta simplicicaulis |
|
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purple everlasting-cudweed, spoon-leaf cudweed, spoon-leaf purple everlasting |
simple-stem cudweed, simple-stem everlasting |
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Habit | Annuals (sometimes winter annuals), 10–40(–50) cm; fibrous-rooted or taprooted. | Annuals or biennials, (30–)50–85 cm; fibrous-rooted. |
Stems | erect to decumbent-ascending, densely but loosely pannose or pannose-tomentose. |
erect or ascending (usually 1, sometimes 2–5), densely and closely white-pannose. |
Leaves | basal and cauline, basal and proximal cauline usually withering before flowering; blades oblanceolate to spatulate, 1–6 cm × 5–14 mm (distal similar, at least among proximal heads, margins sometimes sinuate), faces usually bicolor, abaxial closely white-pannose, adaxial usually sparsely arachnose (basal cells of hairs persistent, expanded, glassy), sometimes glabrescent. |
basal and cauline, basal usually withering before flowering, blades oblanceolate to oblanceolate-spatulate, 5–9 cm × 6–18 mm (gradually smaller distally, margins closely undulate, nearly crenulate; distal cauline linear-lanceolate to linear-oblanceolate, apices long-acute; sessile clusters of smaller leaves produced in axils of mid and distal cauline leaves), faces bicolor, abaxial closely white-pannose, adaxial glabrous (shiny). |
Involucres | turbinate-cylindric, 4–4.5 mm, bases sparsely arachnose. |
cylindro-campanulate, 3–3.5 mm, bases glabrous. |
Florets | bisexual 3–4; all corollas usually purplish distally. |
bisexual (2–)3; all corollas yellowish distally. |
Phyllaries | in 4–5 series, outer ovate-triangular, lengths 1/3–2/3 inner, apices acute-acuminate, inner triangular-lanceolate (usually striate), laminae purplish (in bud) to whitish or silvery (in fruit), apices acute (not apiculate). |
in 4–6 series, outer ovate to oblong, lengths 1/3–1/2 inner, apices acute-acuminate, inner narrowly oblong, laminae brownish to tan (not purplish), apices acuminate-apiculate. |
Heads | initially in continuous spiciform arrays 1–4(–5) cm × (5–)10–15 mm, later interrupted (glomerules widely separated, bracteate, the proximal often on relatively long peduncles). |
in interrupted, spiciform arrays (8–)16–30 cm × 10–14 mm (pressed; sometimes with ascending, lateral branches, glomerules usually subtended by ± patent linear bracts longer than the glomerules). |
Cypselae | (tan) 0.6–0.7 mm. |
(tan) 0.5–0.6 mm. |
2n | = 14, 28. |
|
Gamochaeta purpurea |
Gamochaeta simplicicaulis |
|
Phenology | Flowering Apr–May(–Jun). | Flowering (Jun–)Jul–Aug(–Oct). |
Habitat | Open, usually disturbed, commonly sandy habitats, roadsides, fields, woodland clearings and edges | Open sites, sandy soil, roadsides, fields, open woods, dunes |
Elevation | 5–300 m (0–1000 ft) | 0–10 m (0–0 ft) |
Distribution |
AL; AR; AZ; CT; DC; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MO; MS; NC; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; WV; HI; ON; Mexico; South America; West Indies; Central America (Nicaragua)
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AL; FL; GA; NC; SC; South America; naturalized in New Zealand; Australia; Java [Introduced in North America] |
Discussion | Gamochaeta purpurea apparently is native to North America and adventive elsewhere. Basal cells of hairs on adaxial faces of leaves are expanded and glassy (versus hairs filiform to bases in most other species) and are diagnostic for Gamochaeta purpurea. From Maryland northward, plants of G. purpurea produce relatively small basal rosettes and relatively shallow fibrous roots or a filiform taproot; southward and southwestward, the basal rosettes often are larger and the fibrous roots are denser. Gamochaeta purpurea apparently occurs widely through the world as a weed; it is fairly clearly native to eastern North America, where it is the least weedy of the gamochaetas. Plants of G. purpurea in southern Arizona along perennial streams at the base of the Santa Catalina Mountains were first collected in 1903 (G. L. Nesom 2004) and were, perhaps, accidentally established through visitation; the same sites are heavily infested by other, more aggressive, nonnative species. Collections of G. purpurea also have been made at higher elevations in the Santa Catalina, Rincon, and Chiricahua mountains, where the species is less likely to have been introduced by human activity. It also seems unlikely that plants in scattered Mexican localities were introduced there by human activity. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Gamochaeta simplicicaulis was reported from North America by G. L. Nesom (1999b, 2000b) as an apparently recent adventive. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 19, p. 433. | FNA vol. 19, p. 434. |
Parent taxa | Asteraceae > tribe Gnaphalieae > Gamochaeta | Asteraceae > tribe Gnaphalieae > Gamochaeta |
Sibling taxa | ||
Synonyms | Gnaphalium purpureum, G. rosacea, Gnaphalium rosaceum | Gnaphalium simplicicaule, Gnaphalium purpureum var. simplicicaule |
Name authority | (Linnaeus) Cabrera: Bol. Soc. Argent. Bot. 9: 377. (1961) | (Willdenow ex Sprengel) Cabrera: Bol. Soc. Argent. Bot. 9: 379. (1961) |
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