Jepson eFlora: Key page
Vascular Plants of California
Key to families | Table of families and genera

Key to Gamochaeta

View taxon page for Gamochaeta

(For a list of species in Gamochaeta, use the above link.)

Jepson Manual glossary definitions can be seen by moving your cursor over words underlined with dots.

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

2. Adaxial  face ± glabrous;  ± purple, 2.5–3 mm, base glabrous; outer phyllaries elliptic-obovate to widely ovate-elliptic, rounded to 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,  to ovate-lanceolate or widely ovate-triangular, truncate-rounded or  to ; disk flowers (3)4–6; fruit 0.5–0.8 mm

3. Involucre 3–3.5 mm;  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  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 , 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.) . Jepson eFlora, [accessed on ]

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

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