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1 Receptacle paleate (bearing receptacular bracts which individually subtend at least some of the flowers of the head). |
..2 Involucres absent or vestigial, usually with 0 phyllaries; heads very small, < 6 mm high, < 4 mm wide; annuals, < 4 dm tall; disc corollas hidden or dingy in color; [tribe Gnaphalieae] |
....3 Bisexual flowers (1-) 2-10 (-11), pappus of (11-) 13-28+ bristles visible in heads; functionally staminate flowers 0. |
......4 Receptacles cylindric to clavate (5-15× as tall as the diameter); most pistillate paleae open to ± folded (at most each enfolding, not enclosing a floret; apices acuminate to aristate); innermost paleae erect to ascending in fruit; cypselae mono- morphic (the outer ± equaling the inner) |
......4 Receptacles fungiform to obovoid (0.4-1.6× as tall as the diameter); most pistillate paleae ± saccate, each ± enclosing a floret, apices blunt; innermost paleae spreading in fruit; cypselae dimorphic (the outer longer than the inner) |
....3 Bisexual flowers 0 or 2-7, pappi 0; functionally staminate flowers 0 or 2-5, pappi 0 or of 1-10 (-13) bristles hidden in heads |
........5 Paleae of the bisexual or staminate flowers flat to concave, not enclosing florets, apices entire; cypselae glabrous; [mainly west of the Mississippi River, rarely east (as in MS, AL, GA, and SC] |
........5 Paleae of the bisexual flowers saccate, each enclosing a floret, apices 2-fid or 3-fid; cypselae (at least the outer) strigose; [se. Texas] |
..2 Involucres present, conspicuous, of many phyllaries; heads larger, 2-20+ mm wide; perennials or coarse annuals, 2-25 dm tall; disc corollas apparent, yellow, white, or pink to purplish. |
..........6 Disc flowers yellow or greenish yellow; [either native of s. TX southwards, or a waif] |
............ 7 Phyllary margins and tips scarious; fresh foliage aromatic |
............ 7 Phyllary margins and tips herbaceous; fresh foliage not aromatic |
..........6 Disc flowers white or whitish to pink or purple; [collectively widespread]. |
............ ..8 Heads in corymbiform arrays; heads bisexual; involucres not burlike or nutlike, lacking tubercles or hooked or straight prickles or spines; leaves lanceolate, unlobed, cuneate at base |
............ ....9 Heads lacking ray flowers; disc flowers pink (rarely nearly white); [Coastal Plain; FL and GA] |
............ ....9 Heads with 5 white (fading to cream), scoop-shaped, inconspicuous ray flowers (keyed here as a 'failsafe'); disc flowers white; [widespread in our region] |
............ ..8 Heads in spiciform or racemiform arrays; heads unisexual (each head either with only female or only male flowers); involucres burlike, with tubercles or straight or hooked spines or prickles; leaves ovate or broader (in outline), often pinnatifid or bipinnatifid, truncate, cordate, or cuneate at base; [collectively widespread in our region]. |
............ ......10 Involucres of pistillate heads (burs) 1-4 mm long, with (1-) 5-12+ straight spines; larger leaves bipinnatifid |
............ ......10 Involucres of pistillate heads (burs) 10-40 mm long, with 30-75+ hooked prickles; phyllaries larger leaves pinnatifid or unlobed |
1 Receptacle epaleate (lacking receptacular bracts individually subtending flowers, but the receptacle sometimes bearing bristles, setae, hairs, or pits with laciniate margins. |
............ ........11 Flowers white, pink, purple, or bluish. |
............ ..........12 Annuals, (1-) 2-10 (-30+) cm tall; corollas whitish, inconspicuous, absent on most of the (pistillate) flowers; leaves 2-3× pinnati-palmately lobed into linear segments; cypselae with an apical spine |
............ ..........12 Perennials, 10-150 cm tall; corollas at least light pink and often darker pink, purple, or blue, conspicuous, present on all flowers; leaves pinnately lobed or entire, the segments not linear; cypselae not spined. |
............ ............ 13 Heads ovoid, 10-21 mm long; flowers 15-40 mm long, with long, narrow lobes; phyllaries >30, in 6+ series, and the apices often with a fringe of appendages and/or a spine tip; basal and lower stem leaves usually pinnately lobed (to entire and unlobed); [widespread in our region, especially northwards] |
............ ............ 13 Heads cylindrical, 2-6 mm long; flowers ca. 3 mm long, with deltate lobes; phyllaries 12-15 in 2-3 series, herbaceous and unadorned; basal and lower stem leaves entire and unlobed; [Coastal Plain of FL and GA] |
............ ........11 Flowers yellow, cream, or rarely red-tinged. |
............ ............ ..14 Leaf blades unlobed. |
............ ............ ....15 Heads 3-4 (-6) mm in diameter, solitary; plants 0.3-3 dm tall; [ballast waif, especially in wet, saline places] |
............ ............ ....15 Heads (3-) 5-20+ mm in diameter, solitary or borne in corymbiform or paniculiform arrays; plants 1.5-15 dm tall. |
............ ............ ......16 Involucres 8-20+ mm in diameter; cypselae 1.5-4.5 mm long |
............ ............ ......16 Involucres (3-) 5-8 (-10) mm in diameter; cypselae 1.5-2 mm long |
............ ............ ..14 Leaf blades 1-3× pinnately or palmately lobed into linear or spatulate segments. |
............ ............ ........17 Annual 0.1-5 dm tall. |
............ ............ ..........18 Disc corollas cream to pale yellow, 0.5-0.8 mm long; fresh plants malodorous; [waif] |
............ ............ ..........18 Disc corollas greenish yellow, 1.1-1.3 mm long; fresh plants pineapple-scented; [common weed, especially northwards in our region] |
............ ............ ........17 Perennial, biennial or annual 4-15 dm tall. |
............ ............ ............ 19 Heads borne in paniculiform, racemiform, or spiciform arrays, never flat-topped; flowers < 50 per head |
............ ............ ............ 19 Heads borne in corymbiform arrays; flowers 60-300+ per head |
1 Disc flowers yellow, orange, red, or brownish. |
..2 Leaves 1-2× pinnately lobed into linear or filiform segments. |
....3 Pappus of 16-20 scales |
....3 Pappus of 6-10 scales; [historical waif] |
..2 Leaves unlobed, or if pinnately lobed, the segments broad (> 3 mm wide). |
......4 Receptacle paleate |
......4 Receptacle epaleate. |
........5 Pappus scales rudimentary, crown-like |
........5 Pappus scales conspicuous. |
..........6 Phyllaries 25-125 in 3-9 series; receptacles flat or slightly convex |
..........6 Phyllaries 6-25 (-60) in 2-3 series; receptacles globose. |
............ 7 Stems not winged |
............ 7 Stems winged from node to node |
1 Disc flowers pink, purple, or white |
............ ..8 Receptacle paleate |
............ ..8 Receptacle epaleate. |
............ ....9 Disc flowers 1-5 (rarely more) per head. |
............ ......10 Disc flowers white (rarely cream), 3; heads not aggregated into a secondary cluster subtended by bracts; [se. TX] |
............ ......10 Disc flowers lavender to purple, sometimes so lightly so as to be white, 1-4 (-5+); heads aggregated into clusters of 1-40 heads, subtended by 1-3 bracts; [collectively widespread in our region] |
............ ........11 Heads (1-) 10-40 per secondary cluster, borne in corymbiform arrays; bracts subtending clusters (2-) 3, deltate; pappus of 5 (-6) scales, each aristate |
............ ........11 Heads 1-5+ per secondary cluster, borne in spiciform arrays; bracts subtending clusters 1-2, linear, lanceolate, or spatulate; pappus of 6-10 scales, laciniate or aristate |
............ ....9 Disc flowers (2-) 10-100+ per head (at least most heads with >10 flowers). |
............ ..........12 Phyllaries 5-15 (-21) in 1-2 (-3) series. |
............ ............ 13 Involucres 2-3 mm in diameter; flowers 7-10 per head; [Coastal Plain, FL and GA] |
............ ............ 13 Involucres 4-15+ mm in diameter; flowers 20-80 per head; [SC, GA, and FL westwards] |
............ ..........12 Phyllaries 18-many in 5+ series. |
............ ............ ..14 Phyllary tips modified into a spine or into an enlarged, lacerate or pectinate network or fringe; receptacle epaleate, but densely bristly; [tribe Cynareae]. |
............ ............ ....15 Heads discoid, all flowers similar |
............ ............ ......16 Pappus normally of plumose bristles (and keyed elsewhere), but sometimes reduced to scales or awns |
............ ............ ......16 Pappus of an outer setiform scales (appearing as "flattened bristles" |
............ ............ ....15 Heads disciform or radiant, the outer flowers of the head sterile, with long lobes, appearing like false rays |
............ ............ ........17 Plant a perennial; flowers pink to purple, flowering Jun-Oct |
............ ............ ........17 Plant an annual; flowers pale to medium blue, flowering Apr-Jun |
............ ............ ..14 Phyllary tips not so modified, unarmed and unelaborate; receptacle epaleate and naked; [tribe Vernonieae]. |
............ ............ ..........18 Peripheral flowers of the heads enlarged and bilaterally symmetrical, appearing like "false rays" |
............ ............ ..........18 Peripheral flowers of the heads similar to the interior flowers, all disc flowers. |
............ ............ ............ 19 Annuals; cypselas not ribbed |
............ ............ ............ 19 Perennials; cypselas 8-10-ribbed. |
............ ............ ............ ..20 Heads each subtended by 3-8 leafy bracts; pappus of narrow scales only, quickly falling |
............ ............ ............ ..20 Heads not subtended by leafy bracts; pappus of an inner series of scales or bristles and an outer series of bristles, persistent |
1 Pappus absent, or of crowns (coroniform) or scales (the scales entire, erose, aristate, or occasionally lacerate, but ultimately with broadened bases compared to bristles). |
..2 Stems usually winged from decurrent leaf bases (except H. amarum, which bares stems with copious, mostly entire, linear leaves) |
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......4 Phyllaries in (3-) 4-9+ series, usually with apices hooked or looped; pappus of setiform awns or scales but falling (thus sometimes appearing absent post maturation) |
......4 Phyllaries in 2-4 series, usually with apices not notably hooked or looped; pappus absent entirely (not just falling). |
........5 Receptacles pitted and hairy (the hairs swollen and apically hooked); [primarily native in western portion of our area] |
........5 Receptacles not pitted, nor hairy; [waifs]. |
..........6 Leaves usually 1-3 pinnately lobed; receptacles epaleate |
..........6 Leaves entire or sometimes toothed, but not pinnately lobed; receptacle epaleate or sometimes with short bristles or setae |
....3 Pappus coroniform or of scales. |
............ 7 Heads smaller, the involucres (excluding phyllary apices) 0.8-7.5 mm in diameter. |
............ ..8 Ray floret laminae fan-shaped and apically 3 or 5 lobed (the laminae sometimes very short and not surpassing phyllary length in Hymenoxys). |
............ ....9 Cauline leaves pronounced, simple or with 3-19+ lobes (the lobes linear-filiform); cypselae villous or pubescent (rarely glabrous); heads radiant, sometimes appearing nearly discoid due to diminutive or inconspicuous ray florets |
............ ....9 Leaves strongly basally-disposed (except T. linearifolia, with basal and cauline leaves, the cauline leaves not with linear lobes), entire or with 2-6 teeth (or sometimes lobes); cypselae moderately to densely pubescent; heads clearly radiate |
............ ..8 Ray floret laminae not apically 3-5 lobed. |
............ ......10 Leaves pinnately compound with linear leaf segments 1-3 mm wide (if not pinnate as in T. tephroleuca, then plants ashy white subshrubs); calyculus present (occasionally absent), of linear bracts subtending the involucre; plants with translucent oil glands evident throughout most parts; [subtribe Pectidinae] |
............ ......10 Leaves simple (if also sometimes subshrubs, these not ashy white as in Gutierrezia); calyculus absent; plants sometimes gland-dotted on leaves (or sometimes also with resinous phyllaries, but not with oil glands throughout). |
............ ........11 Plants annual, with a strong terpenoid smell when crushed, the leaves and phyllaries glutinous; phyllaries 12-15 in 1-2(-3) series |
............ ........11 Plants annuals, biennials, or perennials, if annuals then not bearing a strong terpenoid smell when crushed, the leaves sometimes glutinous but not also the phyllaries; phyllaries 4-40 in 2-4 series ( Gutierrezia) or 5-12 in 1-2 series ( Psilostrophe). |
............ ..........12 Stems glabrous, or papillate-scabrous (but not clearly gray-green in appearance); involucre 1.5-5.5 mm in diameter; plants either annuals or subshrubs; phyllaries 4-40 in 2-4 series |
............ ..........12 Stems arachno-villous, appearing gray-green; involucre 4-7 mm in diameter; plants biennials or perennials; phyllaries 5-12 in 1-2 series |
............ 7 Heads larger, the involucres (8-) 10-20+ mm in diameter. |
............ ............ 13 Phyllaries in (3-) 4-9+ series; cypselae glabrous; leaves often toothed (and also often ovate to oblanceolate). |
............ ............ ..14 Pappus in 2 series, the outer of 25-40 barbellate bristles, the inner of 8-15+ setiform awns or subulate scales 7-10 mm long |
............ ............ ..14 Pappus in 1 series, of mostly 2-3 smooth to setiform awns OR subulate scales 2.5-8 mm long (sometimes with up to 6-8 total barbellulate/setiform awns in G. squarrosa, G. lanceolata, and G. texana) |
............ ............ 13 Phyllaries in 2-3 series (2-3+ in Gaillardia); cypselae villous or otherwise sparsely to densely pubescent; leaves entire, toothed, or sometimes pinnately lobed (the lobes linear, as in Hymenoxys). |
............ ............ ....15 Receptacles entirely epaleate, not bearing any minute setae; ray florets (apical portion of the laminae) 3-5 lobed. |
............ ............ ......16 Cauline leaves pronounced, simple or with 3-19+ lobes (the lobes linear-filiform); cypselae villous or pubescent (rarely glabrous); heads radiant, sometimes appearing nearly discoid due to diminutive or inconspicuous ray florets |
............ ............ ......16 Leaves strongly basally-disposed (except T. linearifolia, with basal and cauline leaves, the cauline leaves not with linear lobes), entire or with 2-6 teeth (or sometimes lobes); cypselae moderately to densely pubescent; heads clearly radiate |
............ ............ ....15 Receptacles typically with spine-like setae or enations (except Gaillardia aestivalis) or very short bristles (i.e. not appearing "chaffy" overall, but these setae apparent upon dissection of the heads); ray florets (apical portion of the laminae) either unlobed ( Amblyolepis) or 3-5 lobed ( Gaillardia). |
............ ............ ........17 Plants sweet-scented; cypselae prominently 10-ribbed; pappus scale apices rounded to acuminate but never aristate; heads borne singly or in paniculiform arrays; ray florets (the laminae) yellow; phyllaries usually not strongly reflexed in fruit |
............ ............ ........17 Plants not sweet-scented; cypselae ca. 4-angled but lacking numerous prominent ribs; pappus scale apices often aristate; heads borne singly; ray florets (the laminae) often bicolored; phyllaries usually strongly reflexed in fruit |
1 Pappus of barbellate to barbellulate bristles (sometimes also with shorter outer scales). |
............ ............ ..........18 Phyllaries in one series. |
............ ............ ............ 19 Plants herbaceous vines; flowers conspicuously orange; calyculus of lanceolate-filiform bractlets; [non-native, FL and TX] |
............ ............ ............ 19 Plants not herbaceous vines; flowers primarily yellow (sometimes yellow-orange); calyculus absent (or 1-2 indistinct bractlets); [natives or non-natives, collectively widespread] |
............ ............ ............ ..20 Pappus bristles red, brown, or purple colored; flowers yellow to yellow-orange; [waif, MD] |
............ ............ ............ ..20 Pappus bristles white; flowers primarily yellow; [native and non-native, widespread] |
............ ............ ............ ....21 Disc florets sterile; stems bracteate but lacking leaves, the leaves simple; [non-native of disturbed habitats, ne US] |
............ ............ ............ ....21 Disc florets fertile; stems with leaves, the leaves simple to pinnately lobed (or otherwise compound); [natives and non-natives, widespread and of both intact and disturbed habitats]. |
............ ............ ............ ......22 Stem leaves deeply toothed, pinnately lobed, or otherwise compound, not clasping or weakly so; plants perennial or rarely annuals ( P. glabella) |
............ ............ ............ ......22 Stem leaves shallowly toothed to subentire, conspicuously clasping the stem; plants annuals |
............ ............ ..........18 Phyllaries in 2-8+ series. |
............ ............ ............ ........23 Plants herbaceous vines; flowers conspicuously orange |
............ ............ ............ ........23 Plants not herbaceous vines; flowers primarily yellow (sometimes yellow-orange) |
............ ............ ............ ..........24 Pappus double, of both an inner (more apparent) series of longer bristles and an outer series consisting of short triangular scales or significantly shorter (and often coarser) bristles, these sitting more or less at the base of the inner pappus bristles (in Prionopsisthe outer bristles subtend the inner awns or scales). |
............ ............ ............ ............ 25 Plants usually gland-dotted; phyllaries often looped/hooked; outer bristles subtending inner scales; involucres globose/hemispheric |
............ ............ ............ ............ 25 Plants glabrous, sericeous, or glandular; phyllaries often ascending, sometimes squarrose; pappus scales subtending inner bristles; involucres variously shaped. |
............ ............ ............ ............ ..26 Outer pappus of scales connate, usually forming cups; ray laminae often reduced, 1.5-2+ mm long; [waifs; tribe Inuleae] |
............ ............ ............ ............ ..26 Outer pappus not connate; ray laminae prominent, usually > 3 mm longer; [native, sometimes weedy; tribe Astereae]. |
............ ............ ............ ............ ....27 Ray florets without pappus |
............ ............ ............ ............ ....27 Ray florets with pappus (similar to that of disc florets). |
............ ............ ............ ............ ......28 Leaves parallel-veined, linear and grasslike |
............ ............ ............ ............ ......28 Leaves pinnately veined, usually broader and not grass-like. |
............ ............ ............ ............ ........29 Plants biennials or perennials, with taproots or fibrous-rooted; phyllaries linear-lanceolate to oblanceolate; inner pappus whitish to stramineous, outer pappus linear to narrowly-triangular |
............ ............ ............ ............ ........29 Plants annuals with taproots; phyllaries linear to linear-lanceolate; inner pappus yellow to rust-colored proximally, outer pappus scale-like; disc florets bisexual and fertile ( B. pilosa) or functionally staminate ( B. hirtella) |
............ ............ ............ ..........24 Pappus simple, of only bristles and not with an additional series of reduced bristles or scales (sometimes pappus in 2-4 unequal series, or outer bristles progressively shortened in Xanthisma). |
............ ............ ............ ............ ..........30 Leaves toothed and tipped with spines (spinulose). |
............ ............ ............ ............ ............ 31 Phyllaries spine-tipped with accompanying white margins (if lacking spine tips as in X. texanum, then inner phyllaries abruptly enlarged into ovate or sometimes elliptic blades 2-5 mm wide) |
............ ............ ............ ............ ............ 31 Phyllaries not spine-tipped and lacking conspicuous white margins, 0.9-1.7 mm wide. |
............ ............ ............ ............ ..........30 Leaves entire or if toothed, not tipped with conspicuous spines (as in Grindelia). |
............ ............ ............ ............ ............ ..32 Ray florets longer, 1.5-3+ cm long; anthers tailed; leaf bases conspicuously cordate-clasping |
............ ............ ............ ............ ............ ..32 Ray florets shorter, < 1.5 cm long (to 1.6 cm in Grindelia lanceolata); anthers not tailed (instead obtuse to sagittate), or if sagittate-tailed, then plants foul-smelling (as in Dittrichia, a waif in ne. US). |
............ ............ ............ ............ ............ ....33 Plants viscid, foul-smelling; anthers sagittate-tailed at the base [waif, ne. US] |
............ ............ ............ ............ ............ ....33 Plants scentless, or if bearing an odor, not foul-smelling; anthers cuneate to sagittate at the base, but not tailed; [widespread natives, rarely e. US waifs otherwise native to w. US]. |
............ ............ ............ ............ ............ ......34 Pappus bristles > 60 (30-80+ in Senecio), white-colored. |
............ ............ ............ ............ ............ ........35 Stem leaves deeply toothed, pinnately lobed, or otherwise compound, not clasping or weakly so; plants perennial or rarely annuals ( P. glabella) |
............ ............ ............ ............ ............ ........35 Stem leaves shallowly toothed to subentire, conspicuously clasping the stem; plants annuals |
............ ............ ............ ............ ............ ......34 Pappus bristles 10-45 (30-80+ in Senecio), white, tawny, or reddish-brown colored. |
............ ............ ............ ............ ............ ..........36 Phyllaries in 1-2 equal/subequal series (outer minute bracts sometimes present); stem leaves shallowly toothed to subentire, conspicuously clasping the stem; plants annuals; [tribe Senecioneae) |
............ ............ ............ ............ ............ ..........36 Phyllaries in 3+ series, unequal (or rarely subequal); [tribe Astereae]. |
............ ............ ............ ............ ............ ............ 37 Heads small and cylindrical, taller than wide; rays inconspicuous or the laminae often shorter. |
............ ............ ............ ............ ............ ............ ..38 Inflorescences flat-topped corymbs; leaves resinous-punctate, narrow, entire, sessile or subsessile |
............ ............ ............ ............ ............ ............ ..38 Inflorescences rarely flat-topped; leaves not resinous-punctate, usually not linear, often toothed and petiolate |
............ ............ ............ ............ ............ ............ 37 Heads larger, globose, hemispheric, or broadly conic (2 cm+ broad in Grindelia), usually wider than long; rays conspicuous. |
............ ............ ............ ............ ............ ............ ....39 Leaves entire, sessile throughout; faces of cypselae strigose to sericeous; pappus persistent, of 30-35 tawny to reddish-brown barbellate bristles |
............ ............ ............ ............ ............ ............ ....39 Leaves toothed, proximal leaves petiolate; faces of cypselae variously textured (smooth, striate, furrowed, or rugose); pappus readily falling, of 2-3 smooth to setiform awns OR subulate scales 2.5-8 mm long (sometimes with up to 6-8 total barbellulate/setiform awns in G. squarrosa, G. lanceolata, and G. texana) |
