1	"Rays white to pink or purple"	2
1	"Rays yellow to orange (sometimes multi-colored)"	10
2	"Disk corollas white or pink"	3
2	"Disk corollas yellow"	4
3	"Leaves finely dissected, aromatic; heads many in flat-topped clusters; rays ovate to round"	"Achillea {Achillea millefolium}"
3	"Leaves entire or toothed, not aromatic; heads solitary or in small cymes; rays narrowly linear"	"Eclipta {Eclipta prostrata}"
4	"Leaves entire or toothed"	5
4	"Leaves pinnately lobed or dissected to compound"	6
5	"Leaves opposite, +- ovate"	"Galinsoga {Galinsoga parviflora var. parviflora}"
5	"Leaves alternate, linear or lance-linear to narrowly oblanceolate"	"Rigiopappus {Rigiopappus leptocladus}"
6	"Phyllaries in 2 very different series [inner +- membranous]"	7
6	"Phyllaries graduated in 2--several series, unequal, margins scarious or transparent"	8
7	"Leaves pinnate; leaflets flat, serrate; rays short, inconspicuous"	"Bidens pilosa"
7	"Leaves 1--3-pinnately dissected, segments narrowly linear, entire; rays long, conspicuous"	Cosmos
8	"Fruit initially hairy, densely tomentose in age"	"Lasiospermum {Lasiospermum bipinnatum}"
8	"Fruit glabrous"	9
9	"Base of corolla narrow"	Anthemis
9	"Base of corolla wide, enclosing fruit tip"	"Chamaemelum {Chamaemelum fuscatum}"
10	"Paleae flat, linear to ovate, not folded around disk ovaries"	11
10	"Paleae each folded around a disk flower ovary"	16
11	"Phyllaries +- alike, in 2+ series"	12
11	"Phyllaries in 2 very different series, outer with leaf-like texture, inner +- membranous"	14
12	"Phyllaries graduated in several series, unequal, margins scarious or transparent --- pappus crown-like, generally 0.2--0.3 mm"	"Cota {Cota tinctoria}"
12	"Phyllaries not strongly graduated, +- equal, margins not scarious or transparent (except inner phyllaries of <i>Rigiopappus</i>)"	13
13	"Leaves oblong to ovate, entire to pinnately lobed; pappus scales awn-tipped"	Gaillardia
13	"Leaves linear, entire; pappus scales stiff, tapered"	Rigiopappus
14	"Pappus of awns with reflexed barbs"	Bidens
14	"Pappus 0 or of flat scales"	15
15	"Leaves alternate or all basal; ray flowers fertile"	Leptosyne
15	"Leaves opposite; ray flowers sterile"	Coreopsis
16	"Ray flowers fruiting [style present, ovary well developed]"	17
16	"Ray flowers sterile [style generally 0, ovary vestigial]"	20
17	"Annual; disk fruit compressed, winged"	"Verbesina encelioides subsp. exauriculata"
17	"Perennial herb or subshrub; disk fruit compressed or 3--4-angled, not winged"	18
18	"Leaves mostly +- basal, cauline 0 or few; pappus 0"	Balsamorhiza
18	"Leaves basal and cauline; pappus of scales or 0"	19
19	"Disk corolla +- 5 mm; cauline leaves many"	"Pallenis {Pallenis maritima}"
19	"Disk corolla 8--12 mm; cauline leaves few"	Wyethia
20	"Fruit strongly compressed, margin +- thin"	21
20	"Fruit weakly compressed or not, margin generally not thin"	26
21	"Fruit margin ciliate"	22
21	"Fruit margin not ciliate"	24
22	"Subshrub or shrub"	Encelia
22	"Annual or perennial herb (sometimes with woody caudex)"	23
23	"Leaves all +- basal, gray or silvery, entire"	Enceliopsis
23	"Leaves mostly cauline, green, entire or toothed"	"Geraea canescens"
24	"Leaves all +- basal, silvery or gray; fruit margin corky"	Enceliopsis
24	"Leaves basal and cauline or all cauline, green; fruit margin thin or winged"	25
25	"Perennial herb; leaves basal and cauline, entire"	Helianthella
25	"Subshrub; leaves cauline, some often toothed"	"Verbesina dissita"
26	"Receptacle widely cylindric to conic or +- spheric; disk corollas yellow-green or dark brown-purple"	27
26	"Receptacle generally flat to convex, if conic, disk corollas yellow or yellow-orange"	28
27	"Involucre at early flower 8--16 mm diam; fruit compressed, ciliate abaxially --- phyllary series unequal, outer >> inner"	"Ratibida {Ratibida columnifera}"
27	"Involucre at early flower 15--30+ mm diam; fruit not compressed, not ciliate abaxially"	Rudbeckia
28	"Pappus 0"	"Heliomeris {Heliomeris multiflora var. nevadensis}"
28	"Pappus present"	29
29	"Herb (subshrub); pappus scales generally readily deciduous"	Helianthus
29	"Subshrub or shrub; pappus scales persistent or readily deciduous (if subshrub, pappus persistent)"	30
30	"Leaf oblong or narrowly lanceolate to ovate or triangular, base obtuse or rounded to truncate or cordate"	Bahiopsis
30	"Leaf elliptic to widely obovate, base tapered, wedge-shaped"	"Viguiera {Viguiera purisimae}"