Annuals, biennials, or perennials, 3–100+ cm (rhizomatous or taprooted, often with relatively thin, branched fibrous roots). Stems single or clustered. Leaves basal and cauline (gradually or abruptly reduced distally); alternate; petiolate (mostly basal) or sessile; blades pinnately nerved, elliptic, lanceolate, linear, lyrate, orbiculate, ovate, reniform, or spatulate (and most intermediate shapes, blades often pinnately lobed to pinnatifid or pinnatisect), ultimate margins entire or crenate, dentate, or serrate to denticulate (callous denticles relatively few or 0). Heads radiate or discoid, borne singly or in compact or congested to open, corymbiform, cymiform, or subumbelliform arrays. Calyculi 0 or 1–5+ bractlets. Involucres campanulate to cylindric, 5–12 mm diam. Phyllaries persistent, usually 8, 13, or 21(–30+) in 1–2 series, erect (reflexed in fruit), distinct, (light to dark green, yellowish, reddish, or cyanic) linear to ensiform, equal to subequal (glabrous or hairy), margins usually ± scarious. Receptacles flat, foveolate, epaleate. Ray florets 0 or (1–)5–13, pistillate, fertile; corollas pale yellow to orange-red (tubes 1–4 mm, laminae 4–16 mm). Disc florets 20–80+, bisexual, fertile; corollas pale yellow to deep orange-red, tubes shorter than to equaling campanulate throats, lobes 5, erect to recurved, usually ± deltate; style branches stigmatic in 2 lines, apices usually truncate-penicillate. Cypselae cylindric, usually 5–10-ribbed (ribs usually prominent), glabrous or hirtellous; pappi readily falling, of ± 60+, white, barbellulate bristles. x = 20, 22, 23.


Subtropical, temperate, and arctic regions of North America, 1(–2) species reported from Siberia.


Species 64 (54 in the flora).

Packera is a segregate of Senecio. It contains species that have traditionally been referred to as the “aureoid senecios,” an informal group first recognized by Asa Gray. Base chromosome numbers of x = 22 or 23 and a suite of morphologic characters have been used in circumscription of Packera. Studies involving molecular data and palynological analysis lend additional support for recognition of the genus.

Some species of Packera are abundant and widely distributed, thriving in disturbed habitats. Others are narrow endemics, restricted to specialized habitats, or isolated on mountain peaks. Some species from the latter group are listed as threatened or endangered; others are in need of further study to determine their conservation status.

Species boundaries in Packera are imprecise. Some species hybridize to some extent with others whenever they come into contact; other species or species groups provide taxonomic problems that have yet to be resolved. Authors of relatively recent studies of the widespread P. streptanthifolia and P. paupercula propose dividing the species into varieties based on subtle differences in vegetative morphology and population-level differences in chromosome numbers. In this treatment, while recognizing the value of such work in elucidating evolutionary relationships, I do not discuss most of those proposed varieties. Some of the characteristics used to separate the varieties are overlapping or not readily discernible.

Identification of a given specimen may be reached at multiple points within the key.


1 Plants usually glabrous or glabrate (at most arachnose to tomentose at bases of stems, in axils of leaves, and/or at bases of heads); basal leaves usually entire or dentate, seldom pinnately lobed, pinnatifid, or pinnatisect > 2
1 Plants usually tomentose, sometimes glabrous, glabrate, or glabrescent and/or basal leaves pinnately lobed, pinnatifid, or pinnatisect > 32
2 Plants 3–20(–30+) cm; heads usually 1–6+; arctic or alpine to subalpine > 3
2 Plants 20–100 cm; heads (2–)6–20(–100+); relatively low latitudes to arctic, never alpine > 11
3 Heads (1–)3–6+; ray florets 0 or 8–13 (corolla laminae 6–10+ mm); calyculi conspicuous or inconspicuous (bractlets with swollen bases or cyanic only at tips) > 4
3 Heads 1–2(–5+); ray florets 0 or 10–13 (corolla laminae 7–14 mm); calyculi conspicuous (bractlets usually deeply cyanic to purple-tinged) > 6
4 Cauline leaves gradually reduced (mid and distal sometimes as large as or larger than basal, usually clasping, sometimes auriculate) Packera dimorphophylla
4 Cauline leaves abruptly reduced (clasping or not, not auriculate) > 5
5 Basal leaves (relatively thick and turgid) elliptic-ovate or suborbiculate to spatulate; peduncles ebracteate, glabrous; calyculi inconspicuous Packera malmstenii
5 Basal leaves (not thick or turgid) ovate, oblanceolate, or spatulate; peduncles bracteate, lanate-tomentose; calyculi conspicuous Packera hesperia
6 Basal leaves: blades reniform to subreniform, bases abruptly contracted to cordate, margins crenate or wavy > 7
6 Basal leaves: blades mostly ovate, obovate, oblanceolate, or spatulate, sometimes elliptic, lyrate, or reniform, bases usually tapering to cuneate, sometimes contracted, margins subentire to crenate-dentate, dentate, or weakly lobed to pinnatifid > 8
7 Plants 3–10 cm (rhizomes 5–15+ cm, slender); stems glabrous; disc florets 40–50+ Packera porteri
7 Plants 6–25+ cm (rhizomes 1–6 cm, branched, stout); stems glabrous but for bases and leaf axils; disc florets 60–75+ Packera cymbalaria
8 Cypselae hirtellous on ribs Packera hyperborealis
8 Cypselae glabrous > 9
9 Cauline leaves abruptly reduced (lanceolate, weakly clasping, entire or dentate); disc florets 40–55+ Packera subnuda
9 Cauline leaves gradually or abruptly reduced (lanceolate to linear, not clasping, usually pinnatisect or pinnately lobed, rarely entire); disc florets 55–75+ > 10
10 Basal leaves (relatively thick, fleshy): blades usually ovate, oblong, or spatulate, sometimes lyrate; cauline leaves gradually reduced; phyllaries white-tomentose proximally; cypselae 1–1.25 mm Packera contermina
10 Basal leaves (not notably thick or fleshy): blades ovate to obovate, lyrate, or reniform; cauline leaves abruptly reduced; phyllaries glabrous; cypselae 1.5–2 mm Packera cymbalaria
11 Basal leaves (relatively thick and turgid; herbage glaucous) Packera clevelandii
11 Basal leaves (rarely thick and/or turgid; herbage glabrous or tomentose, not glaucous) > 12
12 Ray florets 0 or 8–13 (corolla laminae 2–7 mm) > 13
12 Ray florets 0 or 5–21 (corolla laminae 4–12+ mm) > 15
13 Cauline leaves gradually reduced (pinnately lobed, sinuses relatively deep, round); heads in corymbiform arrays; pappi 4.5–5.5 mm Packera debilis
13 Cauline leaves gradually or abruptly reduced (subentire to shallowly pinnatifid); heads in subumbelliform arrays; pappi 3–4.5 mm > 14
14 Basal leaves (relatively thick and turgid); heads 1–6+; peduncles bracteate (bractlets cyanic or reddish); phyllaries deep red or green (then tips deep red to purple) Packera pauciflora
14 Basal leaves (relatively thin, flaccid); heads 8–20+; peduncles usually ebracteate; phyllaries green with cyanic tips Packera indecora
15 Basal leaves (and proximal cauline): bases abruptly contracted or truncate to strongly cordate or subcordate > 16
15 Basal leaves (and cauline): bases gradually tapering (sometimes obtuse) > 24
16 Basal leaves: blades broadly to narrowly lanceolate, narrowly ovate, or subhastate, margins serrate-dentate or sharply dentate (apices acute) > 17
16 Basal leaves: blades cordate, obovate, orbiculate, ovate, or reniform, margins crenate, dentate, lobed, or wavy (apices rounded) > 18
17 Basal leaves: blades broadly lanceolate to subhastate; heads in subumbelliform arrays; calyculi inconspicuous; disc florets 70–80+;w of Mississippi River Packera pseudaurea
17 Basal leaves: blades narrowly ovate to oblong-lanceolate; heads in loose, corymbiform arrays; calyculi conspicuous; disc florets 50–70+; e of Mississippi River Packera schweinitziana
18 Basal leaves: blades cordate or reniform > 19
18 Basal leaves: blades orbiculate, orbiculate-ovate, or obovate > 21
19 Basal leaves: margins sharply dentate to shallowly lobed; phyllaries dark green with yellow margins (plants fibrous-rooted, not rhizomatous) Packera ganderi
19 Basal leaves: margins crenate, irregularly dentate, wavy, or lobed; phyllaries light green or green with purple or black tips (plants rhizomatous) > 20
20 Cauline leaves abruptly reduced (sometimes clasping, irregularly dentate or crenate); heads 3–8; calyculiconspicuous; phyllaries light green Packera cardamine
20 Cauline leaves gradually reduced (not clasping, lobed, lateral lobes 2–4 pairs); heads 6–20+; calyculi inconspicuous; phyllaries green (tips purple or black) Packera aurea
21 Stems glabrous or sparsely hairy (at bases); peduncles ebracteate or inconspicuously bracteate, glabrous; calyculi 0 or inconspicuous > 22
21 Stems tomentose (at bases and in leaf axils); peduncles conspicuously bracteate, glabrous or sparsely tomentose; calyculi conspicuous > 23
22 Disc florets 40–60+; cypselae 5–6 mm Packera ganderi
22 Disc florets 60–80+; cypselae 1–1.5 mm Packera crocata
23 Plants stoloniferous; cauline leaves gradually reduced (clasping, margins pinnatisect or pinnately lobed) Packera obovata
23 Plants fibrous-rooted; cauline leaves gradually to abruptly reduced (not clasping, margins entire or subentire) Packera streptanthifolia
24 Basal leaves (and proximal cauline): blades obovate, orbiculate, ovate, or suborbiculate (lengths usually 1–2 times widths) > 25
24 Basal leaves (and proximal cauline): blades elliptic, elliptic-ovate, lanceolate, lyrate, oblanceolate, orbiculate, ovate, or spatulate (lengths usually 2–3 times widths) > 27
25 Basal leaves: margins deeply dissected or pinnatifid to pinnately lobed; cauline leaves abruptly reduced (stems subscapiform); phyllaries light green with yellow tips; disc florets 20–30+ (plants rhizomatous) Packera flettii
25 Basal leaves: margins crenate, dentate, or serrate; cauline leaves gradually reduced; phyllaries green or reddish; disc florets 40–65+ (plants fibrous-rooted, sometimes stoloniferous) > 26
26 Stems and leaf axils usually glabrous, sometimes tomentose proximally; heads 8–15+; peduncles conspicuously bracteate, glabrous or proximally tomentose; calyculi conspicuous Packera obovata
26 Stems and leaf axils usually floccose-tomentose, sometimes glabrate; heads 3–9+; peduncles inconspicuously bracteate, loosely tomentose or glabrescent;calyculi 0 Packera hartiana
27 Heads 20–70(–100+); disc corolla tubes 1.5–2 mm, limbs 1.5–2 mm; cypselae 0.75–1 mm Packera anonyma
27 Heads 2–20+; disc corolla tubes 2–5.5 mm, limbs 2–5 mm; cypselae 1–2.5 mm > 28
28 Plants taprooted (caudices woody) > 29
28 Plants fibrous-rooted, rhizomatous, or taprooted (caudices not woody) > 30
29 Basal leaves (and proximal cauline): blades lanceolate or narrowly oblanceolate, margins entire, subentire, or dentate (distally); calyculi conspicuous; phyllaries 6–10 mm, tomentose proximally; cypselae 1.5–2.5 mm Packera tridenticulata
29 Basal leaves (and proximal cauline): blades elliptic-ovate, broadly oblanceolate, or lyrate, margins irregularly and deeply pinnately parted or lobed; calyculi usually 0, sometimes inconspicuous; phyllaries 4–6+ mm, glabrous; cypselae 1–1.5 mm Packera texensis
30 Basal leaves (relatively thick and turgid): blades oblanceolate, orbiculate, ovate, or spatulate; cauline leaves gradually or abruptly reduced (entire or subentire); calyculi conspicuous; disc florets 35–60+ Packera streptanthifolia
30 Basal leaves (relatively thin, not turgid): blades lanceolate to narrowly elliptic; cauline leaves gradually reduced (margins dissected, incised, lacerate, or lobed); calyculi 0 or inconspicuous; disc florets 50–80+ > 31
31 Plants ± rhizomatous (rhizomes weakly branched); stems glabrous or sparsely tomentose proximally; cauline leaves gradually reduced (sessile, dissected, incised, or lacerate); ray corolla laminae (pale yellow) 5–18+ mm Packera paupercula
31 Plants fibrous-rooted; stems glabrous; cauline leaves gradually reduced (sessile, weakly clasping, ± lobed, often sublyrate); ray corolla laminae (deep yellow to orange-red) 6–8+ mm Packera crocata
32 Basal (and cauline) leaves usually pinnately lobed, pinnatifid, or pinnatisect (herbage usually glabrous or glabrate, sometimes persistently tomentose) > 33
32 Basal leaves usually entire or ± dentate, or pinnately lobed (herbage usually tomentose or glabrescent) > 55
33 Ray florets 0 or 1 (corolla laminae ca. 6 mm) > 34
33 Ray florets (rarely 0) 5–13 (corolla laminae 3–15+ mm) > 35
34 Plants 5–10 cm; stems densely white- or gray-tomentose; basal leaves: blades oblanceolate (pinnatifid), 20–30+ × 5–13+ mm, ultimate margins crenate Packera musiniensis
34 Plants 20–50+ cm; stems sparsely tomentose (mostly bases and leaf axils); basal leaves: blades elliptic to ovate or subreniform, 20–40+ × 15–30+ mm, margins subentire to crenate-dentate Packera debilis
35 Stems (and leaves) usually (persistently) tomentose, sometimes glabrescent > 36
35 Stems (and leaves) usually glabrous, sometimes tomentose (mostly bases and leaf axils) > 44
36 Basal leaves (and proximal cauline): blades narrowly elliptic, lanceolate, lyrate, oblanceolate, or sublyrate > 37
36 Basal leaves (and proximal cauline): blades broadly elliptic, obovate, orbiculate, ovate, or spatulate > 40
37 Plants 3–20 cm; heads 1–6; phyllaries purple or with purple streaks > 38
37 Plants 20–60+ cm; heads 6–25+; phyllaries green (tips sometimes red) > 39
38 Stems (not branched) sparsely lanate or tomentose; basal leaves: margins pinnately lobed (lyrate to sublyrate, midribs winged); Arizona Packera franciscana
38 Stems (usually branched distally) sparsely to densely floccose-tomentose; basal leaves: margins irregularly to pinnately lobed; Yukon; Alaska. Packera ogotorukensis
39 Stems (and leaves) tomentose (throughout); basal leaves: margins evenly pinnatifid or pinnatisect; ray florets 6–8 (corolla laminae 5–7 mm); disc florets 30–40+; cypselae glabrous Packera fendleri
39 Stems densely tomentose (at bases, otherwise sparsely tomentose); basal leaves (abaxial faces sometimes sparsely hairy): margins pinnately lobed (sublyrate) to irregularly pinnatisect; ray florets 8–10 (corolla laminae 9–10 mm); disc florets 60–70+; cypselae hirtellous on ribs Packera plattensis
40 Plants taprooted (caudices becoming branched); basal leaves: margins pinnately lobed > 41
40 Plants rhizomatous or fibrous-rooted; basal leaves: margins pinnatifid to irregularly lobed > 42
41 Plants 30–50 cm; basal leaves (early withering): margins pinnately lobed (lateral lobes 2–6+ pairs, terminal lobes coarsely serrate or finely dissected), ultimate margins irregularly and coarsely serrate-dentate or finely dissected Packera eurycephala
41 Plants 15–30 cm; basal leaves: margins pinnately lobed (lateral lobes 1–3 pairs, smaller than terminals), ultimate margins entire or subentire to crenate or wavy Packera ionophylla
42 Plants 3–8 cm (stems purplish); phyllaries cyanic (Arizona) Packera franciscana
42 Plants 8–60+ cm (stems green); phyllaries green (tips sometimes cyanic) > 43
43 Plants 8–15+ cm (often branched distally); heads 1(–3); Yukon; Alaska Packera ogotorukensis
43 Plants 20–60+ cm (not branched); heads 6–20+ (in corymbiform arrays); s Canada; c United States Packera plattensis
44 Plants taprooted > 45
44 Plants rhizomatous or fibrous-rooted > 49
45 Basal leaves: margins pinnately lobed (lateral lobes 6+ pairs or lobing irregular, terminal lobes smaller than laterals) > 46
45 Basal leaves: margins pinnately lobed (lateral lobes 1–6+ pairs, terminal lobes larger than laterals) > 47
46 Basal leaves: blades narrowly lanceolate; peduncles inconspicuously bracteate or ebracteate; calyculi inconspicuous; pappi 3.5–4.5 mm; e of Continental Divide Packera millelobata
46 Basal leaves: blades obovate, oblanceolate, or spatulate; peduncles bracteate; calyculi conspicuous; pappi 5–6 mm; w of Continental Divide Packera multilobata
47 Plants 60–100+ cm (stems deeply purple-tinged at bases, lightly tinged distally); basal leaves: blades pinnately lobed (bases of lateral lobes relatively wide, midribs weakly winged), ultimate margins sharply dentate or irregularly incised Packera quercetorum
47 Plants 20–50 cm (stems sometimes red-tinged at bases); basal leaves: blades pinnately lobed (bases of lateral lobes petioluliform, midribs sometimes winged or toothed), ultimate margins crenate to crenate-dentate > 48
48 Annuals (stems reddish at bases); cauline leaves gradually reduced (often auriculate); peduncles bracteate; disc florets 30–45(–100+); wet, sandy or clay sites, stream banks, waste areas Packera tampicana
48 Perennials (stems green); cauline leaves gradually to abruptly reduced (not auriculate); peduncles ebracteate; disc florets 60–75+; limestone plateaus, granitic sands along roadsides, oak woodlands Packera texensis
49 Basal leaves: margins 2–3 times pinnately dissected Packera millefolium
49 Basal leaves: margins mostly pinnatifid or pinnately lobed > 50
50 Plants 20–70+ cm (stems striated, often hollow, pink to purple tinged) Packera glabella
50 Plants 6–100+ cm (stems not striated or hollow) > 51
51 Plants 6–20 cm; heads 1–2(–5); cypselae hirtellous on ribs (n coastal Alaska, North West Territories, Banks Island, and Yukon) Packera hyperborealis
51 Plants 20–100+ cm; heads 3–50+; cypselae glabrous > 52
52 Plants 40–100+ cm; basal leaves: blades spatulate to obovate (pinnately lobed, lateral lobes 2–6+ pairs, smaller than terminals), ultimate margins dentate to lacerate; heads 15–50+; disc florets 45–60+; dry, rocky soils, oak savannahs Packera breweri
52 Plants 10–50 cm; basal leaves: blades cordate, oblanceolate, obovate, ovate, or subcordate (pinnately lobed or incised, lateral lobes 1–3 pairs, equaling terminals), ultimate margins crenate to dentate; heads 4–15+; disc florets 20–50+; damp, rocky soils, streambeds, meadows > 53
53 Basal leaves: blades broadly oblanceolate (pinnately lobed, bases of terminal and lateral lobes petioluliform, midribs not winged); New Mexico Packera sanguisorboides
53 Basal leaves: blades cordate to subcordate or obovate to ovate (pinnately lobed, bases of terminal and lateral lobes not contracted, sinuses rounded, midribs winged); Oregon, Washington > 54
54 Basal leaves: blades cordate to subcordate; cauline leaves gradually reduced distally (petiolate); heads 8–15+; phyllaries dark green; disc florets 30–45+ Packera bolanderi
54 Basal leaves: blades obovate to ovate; cauline leaves abruptly reduced distally (sessile, stems scapiform); heads 4–10+; phyllaries light green (tips yellowish); disc florets 20–30+ Packera flettii
55 Plants 3–10 cm; heads 1–6(–15+) > 56
55 Plants 10–50+ cm; heads (1–)6–30+ > 64
56 Ray florets 0 or 1–8 (corolla laminae 4–7 mm) > 57
56 Ray florets (0) 8–13+ (corolla laminae 4–16 mm) > 59
57 Basal leaves sessile, blades linear, margins entire (strongly revolute) Packera spellenbergii
57 Basal leaves ± petiolate, blades obovate to oblanceolate or spatulate, margins entire, crenate, or pinnatifid > 58
58 Basal leaves: margins entire or crenate; phyllaries purple-tinged, tomentose (apices with dense tufts of hairs) Packera castoreus
58 Basal leaves: (blades often pinnatifid) ultimate margins crenate; phyllaries yellow-green to purple (or with purplish midstripes), sparsely tomentose (apices rounded) Packera musiniensis
59 Stems (often branched proximally, sometimes distally), sparsely tomentose to densely floccose-tomentose; British Columbia, Yukon; Alaska Packera ogotorukensis
59 Stems (not branched) lanate or canescent, or glabrous, glabrescent, or sparsely tomentose; not Arctic > 60
60 Plants ± rhizomatous (rhizomes branched); stems canescent, floccose-tomentose, lanate, or lanate-tomentose > 61
60 Plants fibrous-rooted (caudices slender) or rhizomatous (rhizomes creeping); stems glabrous, glabrate, arachno-tomentose, sparsely lanate, or sparsely tomentose (then sometimes glabrescent) > 62
61 Cauline leaves gradually reduced (blades similar to basals); cypselae 2.5–3.5 mm Packera cana
61 Cauline leaves abruptly reduced (bractlike); cypselae 1.5–2 mm Packera werneriifolia
62 Basal leaves: blades lyrate to sublyrate (pinnately lobed, midribs winged) or ovate to orbiculate and margins ± dentate; cauline leaves gradually reduced Packera franciscana
62 Basal leaves: blades oblanceolate, ovate, or spatulate, margins entire, subentire, or dentate (toward apices); cauline leaves abruptly reduced (stems often scapiform) > 63
63 Peduncles inconspicuously bracteate, glabrous or densely hairy; calyculi conspicuous (bractlets often cyanic); Rocky Mountains, through Nevada to California (at or above timberline) Packera werneriifolia
63 Peduncles conspicuously bracteate, densely lanate-tomentose; calyculi inconspicuous (bractlets red-tinged); s Oregon Packera hesperia
64 Plants taprooted (caudices often branched) > 65
64 Plants fibrous-rooted or rhizomatous > 68
65 Basal leaves: blades lanceolate or oblanceolate, margins entire or shallowly dentate (slightly revolute) Packera macounii
65 Basal leaves: blades lyrate (pinnately lobed), obovate, broadly ovate, or spatulate, ultimate margins dentate, denticulate, dissected, pinnatifid, subentire, or subserrate > 66
66 Basal leaves: blades ovate to lanceolate or narrowly lanceolate, margins subentire or denticulate to subserrate (abaxial faces often cyanic, usually tomentose, adaxial faces often glabrate) Packera neomexicana
66 Basal leaves: blades often lyrate (pinnately lobed), ultimate margins crenate to irregularly and coarsely dentate (at least toward apices) or pinnatifid (abaxial faces not cyanic, sparsely to densely tomentose) > 67
67 Plants 20–50+ cm; taprooted (caudices branched, ascending to erect, woody); basal leaves (soon withering): blades obovate, ovate, or spatulate (sometimes pinnately lobed to pinnatifid, lateral lobes 2–6+ pairs), ultimate margins irregularly and coarsely dentate Packera eurycephala
67 Plants 15–30+ cm; taprooted (caudices not woody) or rhizomatous (rhizomes branched); basal leaves (persistent): blades ovate, sometimes lyrate (often pinnately lobed, lateral lobes 1–3 pairs), ultimate margins crenate to coarsely dentate (at least toward apices) Packera ionophylla
68 Heads 1–5; ray corolla laminae 8–16 mm > 69
68 Heads (2–)5–30+; ray corolla laminae 5–10(–16) mm > 70
69 Basal leaves: blades orbiculate to ovate or rhombic, margins irregularly dentate; ray florets 8–10 (corollas red-orange, laminae 8–15 mm) Packera greenei
69 Basal leaves: blades narrowly elliptic or lanceolate to oblanceolate, margins entire, subentire, or weakly dentate; ray florets 5 or 8 (corollas yellow, laminae 12–16mm) Packera layneae
70 Stems single (not from rosettes) > 71
70 Stems single (each from a rosette, rosettes usually in clusters of 2–5+) > 72
71 Stems lanate to floccose-tomentose; cauline leaves gradually reduced; heads 10–30+; disc florets 50–60+; pappi 5–7 mm Packera tomentosa
71 Stems tomentose; cauline leaves abruptly reduced; heads 6–12+; disc florets 25–35+; pappi 4–5 mm Packera antennariifolia
72 Basal leaves: blades usually broadly oblanceolate to spatulate, sometimes lanceolate to elliptic (then cypselae 1–1.5 mm and hirtellous on ribs) > 73
72 Basal leaves: blades elliptic, lanceolate, oblanceolate, or obovate (not spatulate) > 75
73 Stems densely lanate to glabrescent; heads in compact, cymiform arrays; calyculi 0; cypselae 0.75–1 mm Packera bernardina
73 Stems sparsely floccose-tomentose, tomentose, or glabrate; heads in corymbiform or subumbelliform arrays; calyculi conspicuous or inconspicuous; cypselae 1–2.5 mm > 74
74 Stems tomentose; calyculi inconspicuous; phyllaries densely tomentose; cypselae hirtellous on ribs Packera antennariifolia
74 Stems usually glabrous, sometimes floccose-tomentose proximally and in leaf axils; calyculi conspicuous; phyllaries glabrous; cypselae glabrous Packera streptanthifolia
75 Basal leaves (relatively leathery, or thick and turgid): blades narrowly elliptic to lanceolate or oblanceolate, margins entire, subentire, or wavy > 76
75 Basal leaves (not leathery, nor thick and turgid): blades elliptic, oblanceolate, orbiculate, ovate, or sublyrate, margins entire, crenate, dentate, serrate, pinnately lobed, or pinnatisect > 78
76 Cauline leaves (relatively leathery) gradually reduced (proximals and mids nearly as large as basals); heads 10–30+ in open or congested, cymiform arrays; peduncles 0 or ebracteate, densely tomentose (usually relatively short) Packera cynthioides
76 Cauline leaves (relatively thick and turgid, not leathery) abruptly or gradually reduced; heads 4–15+ in open, corymbiform, cymiform, or subumbelliform arrays; peduncles bracteate, sparsely tomentose or glabrate > 77
77 Phyllaries dark green proximally, light green distally, floccose-tomentose; ray corolla laminae 12–16 mm; cypselae 2.5–3.5 mm Packera layneae in part)
77 Phyllaries green (tips sometimes cyanic), glabrous; ray corollalaminae 5–10 mm; cypselae 1–2.5 mm Packera streptanthifolia
78 Basal leaves: blades orbiculate to broadly ovate > 79
78 Basal leaves: blades narrowly elliptic, narrowly ovate, or oblanceolate > 80
79 Basal leaves: margins entire, weakly crenate, dentate, or lobed; phyllaries glabrous; cypselae glabrous Packera streptanthifolia
79 Basal leaves: margins dentate to pinnatisect; phyllaries densely tomentose proximally; cypselae usually hirtellous, sometimes glabrous Packera plattensis
80 Basal leaves: margins crenate or serrate-dentate to pinnately lobed, pinnatifid, or pinnatisect > 81
80 Basal leaves: margins entire, subentire, or dentate (toward apices) > 82
81 Plants rhizomatous and/or fibrous-rooted, sometimes stoloniferous (mostly eastern populations); basal leaves: margins dentate or pinnately lobed to pinnatisect; disc florets 60–70+; cypselae usually hirtellous, sometimes glabrous; pappi 6.5–7.5 mm Packera plattensis
81 Plants rhizomatous (rhizomes branched, plants not fibrous-rooted or stoloniferous); basal leaves: margins wavy or evenly pinnatifid to pinnatisect; disc florets 30–40+; cypselae glabrous; pappi 4–5 mm Packera fendleri
82 Stems densely lanate-tomentose or canescent; calyculi inconspicuous; cypselae glabrous Packera cana
82 Stems lanate- or arachno-tomentose or glabrescent; calyculi conspicuous; cypselae usually hirtellous on ribs, sometimes glabrous Packera neomexicana
... more about "Packera"
Debra K. Trock +
Á. Löve & D. Löve +
Ragwort +
Subtropical +, temperate +, and arctic regions of North America +  and 1(–2) species reported from Siberia. +
For John G. Packer, b. 1929, Canadian botanist +
bain1994a +, bain1995a +, bain1996a +, bain1997a +, barkley1962a +, barkley1968a +, barkley1980a +, barkley1988a +, kowal1975a +  and packer1972a +
Compositae +
Packera +
Asteraceae tribe Senecioneae +