Jepson eFlora
Key to families | Table of families and genera

Key to Gamochaeta

View taxon page for Gamochaeta

1. Leaf faces contrasting in color, adaxially ± glabrous to ± cobwebby-tomentose, abaxially white-felty tomentose

2. Adaxial leaf face ± glabrous; involucre ± purple, 2.5–3 mm, base glabrous; outer phyllaries elliptic-obovate to widely ovate-elliptic, rounded to obtuse; disk flowers 2–3; fruit 0.5–0.6 mm ..... G. coarctata

2' Adaxial leaf face ± sparsely cobwebby-tomentose; involucre ± brown, 3–5 mm, embedded in woolly hairs, base often sparsely cobwebby; outer phyllaries and flattened tips of inner dark or ± green-brown, ovate to ovate-lanceolate or widely ovate-triangular, truncate-rounded or acute to acuminate; disk flowers (3)4–6; fruit 0.5–0.8 mm

3. Involucre 3–3.5 mm; head clusters 10–12 mm wide (pressed); outer phyllaries ovate to ovate-lanceolate; fruit 0.5–0.6 mm ..... G. argyrinea

3' Involucre 4.5–5 mm; head clusters 12–18 mm wide (pressed); outer phyllaries widely ovate-triangular; fruit 0.7–0.8 mm ..... G. ustulata

1' Leaf faces not or weakly contrasting in color, ± green or gray-green, loosely tomentose or cobwebby, sometimes ± felty, sometimes adaxially ± glabrous in Gamochaeta stagnalis

4. Basal and proximal cauline leaves 4–16 mm wide; bracts among heads, cauline leaves oblanceolate to spoon-shaped, at least proximal bracts surpassing clusters of heads ..... G. pensylvanica

4' Basal and proximal cauline leaves 2–9 mm wide; bracts among heads, mid to distal cauline leaves generally linear to ± oblanceolate, bracts surpassing heads or not

5. Mid and distal cauline leaves oblanceolate, ± clasping; bracts among heads generally < clusters; involucre 3.5–4 mm; phyllaries in 4–5 series ..... [G. stachydifolia]

5' Mid and distal cauline leaves linear to lanceolate, oblanceolate, or spoon-shaped, not ± clasping; bracts among heads < or > than clusters; involucre 2.5–3.5 mm; phyllaries in 3–4(5) or 5–7 series

6. Involucre 3–3.5 mm, not purple, base generally ± glabrous to occasionally sparsely cobwebby; phyllaries in 5–7 series, outer ovate-triangular, 1/3–1/2 × inner, acute-acuminate; flower Jun–Jul ..... G. calviceps

6' Involucre 2.5–3 mm, generally ± purple proximally, base cobwebby; phyllaries in 3–4(5) series, outer ovate-triangular, 1/2–2/3 × inner, acute; flower Mar–Apr ..... G. stagnalis


Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].
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