Gamochaeta purpurea |
Gamochaeta coarctata |
|
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purple everlasting-cudweed, spoon-leaf cudweed, spoon-leaf purple everlasting |
elegant cudweed, gray everlasting |
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Habit | Annuals (sometimes winter annuals), 10–40(–50) cm; fibrous-rooted or taprooted. | |
Stems | erect to decumbent-ascending, densely but loosely pannose or pannose-tomentose. |
decumbent-ascending, white-pannose (tomentum usually sheath-like). |
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 present (in rosettes) at flowering, blades spatulate to oblanceolate-obovate, (1.5–)3–8(–12) cm × 6–15(–22) mm (gradually or little smaller distally, slightly succulent, margins often crenulate on drying), faces bicolor, abaxial closely white-pannose, adaxial glabrous or glabrate. |
Involucres | turbinate-cylindric, 4–4.5 mm, bases sparsely arachnose. |
cylindro-campanulate, 2.5–3 mm, bases glabrous. |
Florets | bisexual 3–4; all corollas usually purplish distally. |
bisexual 2–3; all corollas usually purplish 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 4–5 series, outer (purplish or rosy) elliptic-obovate to broadly ovate-elliptic, lengths 1/3–1/4 inner, apices rounded to obtuse, inner oblong, laminae brown-hyaline, apices rounded to obtuse or blunt, 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). |
initially usually in dense, continuous spiciform arrays 2–20 cm × 10–14 mm (pressed), later branched, interrupted. |
Cypselae | (tan) 0.6–0.7 mm. |
(tan) 0.5–0.6 mm. |
Winter | annuals or biennials, 15–35(–50) cm; fibrous-rooted. |
|
2n | = 14, 28. |
= 28, 40. |
Gamochaeta purpurea |
Gamochaeta coarctata |
|
Phenology | Flowering Apr–May(–Jun). | Flowering Apr–Jun. |
Habitat | Open, usually disturbed, commonly sandy habitats, roadsides, fields, woodland clearings and edges | Ditches, low roadsides, sidewalk cracks, shaded spots around buildings, other shaded, moist habitats |
Elevation | 5–300 m (0–1000 ft) | 0–150 m (0–500 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; AR; CA; FL; GA; LA; MS; NC; SC; TX; VA; South America [Introduced in North America; also introduced in Mexico, West Indies, Europe, Asia, Pacific Islands (New Zealand), Australia]
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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 coarctata is native to South America and is also introduced in Mexico. R. K. Godfrey (1958) identified specimens of G. coarctata as Gnaphalium spicatum Lamarck. Some specimens from the flora area were misidentified by G. L. Nesom (1990f) as Gamochaeta americana (Miller) Weddell, which was described from Jamaica; it is widespread in Central America and Mexico, and has not been observed in the flora area. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 19, p. 433. | FNA vol. 19, p. 435. |
Parent taxa | Asteraceae > tribe Gnaphalieae > Gamochaeta | Asteraceae > tribe Gnaphalieae > Gamochaeta |
Sibling taxa | ||
Synonyms | Gnaphalium purpureum, G. rosacea, Gnaphalium rosaceum | Gnaphalium coarctatum, G. spicata |
Name authority | (Linnaeus) Cabrera: Bol. Soc. Argent. Bot. 9: 377. (1961) | (Willdenow) Kerguélen: Lejeunia 120: 104. (1987) |
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