Gamochaeta stachydifolia |
Gamochaeta pensylvanica |
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gamochaeta pensylvanica, Pennsylvania cudweed, Pennsylvania everlasting, Pennsylvania everlasting-cudweed |
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Habit | Annuals, 4–15 cm; taprooted. | Annuals, 10–50 cm; taprooted. |
Stems | erect, densely and loosely gray-white tomentose-arachnose. |
erect to decumbent or procumbent, loosely arachnose-tomentose. |
Leaves | basal and cauline, basal mostly withering before flowering, blades oblanceolate, 1–3 cm × 2–6 mm (usually folded along midveins, bases subclasping, not auriculate; nearly unreduced among proximal heads, none longer than glomerules), faces concolor, tomentose-arachnose. |
basal and cauline, proximal usually present at flowering, blades spatulate to oblanceolate-obovate, 2–7 cm × 4–16 mm (becoming spatulate to oblanceolate bracts among proximal heads, surpassing glomerules, bases narrowed to petiolar regions, margins sinuate, apices often apiculate), faces concolor or weakly bicolor, loosely tomentose. |
Involucres | campanulate, 3.5–4 mm, bases sparsely tomentose. |
cupulate-campanulate, 3–3.5 mm, bases sparsely arachnose. |
Florets | bisexual 2–4; all corollas yellowish. |
bisexual 3–4; all (or at least bisexual) corollas usually purplish distally. |
Phyllaries | in 4–5 series, outer narrowly ovate-triangular, lengths ca. 1/3 inner, apices acute to acute-acuminate, inner oblong, laminae tan to brownish (not purple), apices (brownish) rounded-apiculate. |
in 3–4 series, outer ovate-triangular, lengths 1/2–2/3 inner, apices attenuate-apiculate, inner oblong, laminae often purple-tinged (at stereome), apices (transparent, sometimes golden) acute to obtuse. |
Heads | in continuous cylindric arrays 2–3(–4) cm × 10–12 mm (pressed). |
in glomerules in continuous or interrupted, spiciform arrays 1–12 cm × 10–15 mm (pressed). |
Cypselae | not seen. |
(tan) 0.4–0.5 mm. |
2n | = 28. |
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Gamochaeta stachydifolia |
Gamochaeta pensylvanica |
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Phenology | Flowering Mar–May. | Flowering Mar–Jun(–Aug). |
Habitat | Hillsides, riparian woodlands, disturbed sites, sandy soils | Disturbed sites, exposed, moist soils, commonly partially shaded |
Elevation | 30–500 m (100–1600 ft) | 0–500 m (0–1600 ft) |
Distribution |
CA; South America [Introduced in North America] |
AL; CA; FL; GA; LA; MA; MD; MS; NC; OK; PA; SC; TX; VA; Mexico; Central America; South America; Europe; Asia; Africa; Australia
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Discussion | Gamochaeta pensylvanica is recognized by its obovate-spatulate, loosely tomentose and concolor or weakly bicolor basal and proximal cauline leaves, and similarly shaped spreading bracts among the heads. Occasional plants appear intermediate between G. pensylvanica and G. antillana. The latter differs in its more erect stems, linear to oblanceolate basal and proximal cauline leaves, and more nearly continuous arrays of heads with linear to narrowly oblanceolate bracts. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 19, p. 437. | FNA vol. 19, p. 437. |
Parent taxa | Asteraceae > tribe Gnaphalieae > Gamochaeta | Asteraceae > tribe Gnaphalieae > Gamochaeta |
Sibling taxa | ||
Synonyms | Gnaphalium stachydifolium, Gnaphalium purpureum var. stachydifolium | Gnaphalium pensylvanicum, Gnaphalium peregrinum |
Name authority | (Lamarck) Cabrera: Bol. Soc. Argent. Bot. 9: 382. (1961) | (Willdenow) Cabrera: Bol. Soc. Argent. Bot. 9: 375. (1961) |
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