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balsam groundsel, Canadian butterweed

Bolander's groundsel, Bolander's ragwort

Habit Perennials, 20–45+ cm; subrhizomatous (bases weakly branched, ascending to erect). Perennials, 20–50+ cm; fibrous-rooted (caudices creeping).
Stems

1 or 2–4, loosely clustered, glabrous or sparsely tomentose proximally.

1 or 2–3, loosely clustered, glabrous.

Basal leaves

petiolate;

blades lanceolate to narrowly elliptic or oblanceolate, 30–60+ × 10–20+ mm, bases tapering, sometimes obtuse, margins subentire to dentate or serrate.

(and proximal cauline) petiolate;

blades ± orbiculate to oblong, or lyrate (lateral lobes 1–3 pairs, sinuses usually rounded, midribs usually winged), 50–120+ × 30–70+ mm, bases cordate to subcordate, margins shallowly to deeply incised.

Cauline leaves

gradually reduced (proximals petiolate, sublyrate; mids sessile, not clasping, lanceolate, dissected, incised, or lacerate; distals sessile, bractlike).

gradually reduced (petiolate or sessile and clasping; lanceolate, incised).

Peduncles

usually bracteate, sometimes ebracteate, glabrous.

ebracteate or inconspicuously bracteate, glabrous.

Ray florets

0, 8, or 13;

corolla laminae (pale yellow) 5–10+ mm.

8 or 13;

corolla laminae 10–15+ mm.

Disc florets

50–65+;

corolla tubes 2–3 mm, limbs 2–3 mm.

30–45+;

corolla tubes 3–4 mm, limbs 3.5–4.5 mm.

Phyllaries

13 or 21, green, 5–8+ mm, glabrous.

(8), 13, or 21, dark green, 5–8 mm, glabrous or sparsely tomentose proximally.

Calyculi

inconspicuous.

conspicuous.

Heads

2–10+ in loose or compact, corymbiform arrays.

8–15+ in corymbiform or subumbelliform arrays.

Cypselae

1–2 mm, usually glabrous, sometimes hispidulous on ribs;

pappi 3.5–4.5 mm.

2.5–3.5 mm, glabrous;

pappi 5–7 mm.

2n

= 44, 46, 92.

= 46.

Packera paupercula

Packera bolanderi

Phenology Flowering May–late Jun (south), late Jun–early Aug (north).
Habitat Wet meadows, open woodlands, along streams, rocky outcrops
Elevation 0–3000 m (0–9800 ft)
Distribution
from FNA
AK; AL; CO; DC; GA; IA; ID; IL; IN; KY; MA; MD; ME; MI; MN; MT; NC; ND; NH; NJ; NY; OH; PA; SD; TN; UT; VT; WA; WI; WV; WY; AB; BC; MB; NB; NL; NS; NT; NU; ON; PE; QC; SK; YT
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; OR; WA
[WildflowerSearch map]
[BONAP county map]
Discussion

Ecologically and morphologically, Packera paupercula is the most variable species of the genus in North America. Some “phases” have been treated as separate species, subspecies, varieties, forms, and races. Variation within P. paupercula hints at some interesting evolutionary relationships; characteristics used to separate taxa overlap. Much of the morphologic variation in this species may be due to hybridization and introgression. I do not recognize any of the infraspecific taxa that have been proposed.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Varieties 2 (2 in the flora).

The two varieties of Packera bolanderi have been treated as species. The morphologic characteristics used to distinguish the varieties vary widely within some populations. Presence or absence of multicellular hairs has been used to separate the varieties; that trait is also variable. The morphologic distinction is weak; habitat and elevation records lend support for recognizing two varieties.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Basal leaves (relatively thick and turgid); phyllaries 13 or 21, 6–8+ mm, hairy proximally (hairs tan or brownish, multicelled)
var. bolanderi
1. Basal leaves (relatively thin); phyllaries 8, 13, (or 21), 5–6 mm, glabrous
var. harfordii
Source FNA vol. 20, p. 595. FNA vol. 20, p. 579.
Parent taxa Asteraceae > tribe Senecioneae > Packera Asteraceae > tribe Senecioneae > Packera
Sibling taxa
P. anonyma, P. antennariifolia, P. aurea, P. bernardina, P. bolanderi, P. breweri, P. cana, P. cardamine, P. castoreus, P. clevelandii, P. contermina, P. crocata, P. cymbalaria, P. cynthioides, P. debilis, P. dimorphophylla, P. eurycephala, P. fendleri, P. flettii, P. franciscana, P. ganderi, P. glabella, P. greenei, P. hartiana, P. hesperia, P. hyperborealis, P. indecora, P. ionophylla, P. layneae, P. macounii, P. malmstenii, P. millefolium, P. millelobata, P. multilobata, P. musiniensis, P. neomexicana, P. obovata, P. ogotorukensis, P. pauciflora, P. plattensis, P. porteri, P. pseudaurea, P. quercetorum, P. sanguisorboides, P. schweinitziana, P. spellenbergii, P. streptanthifolia, P. subnuda, P. tampicana, P. texensis, P. tomentosa, P. tridenticulata, P. werneriifolia
P. anonyma, P. antennariifolia, P. aurea, P. bernardina, P. breweri, P. cana, P. cardamine, P. castoreus, P. clevelandii, P. contermina, P. crocata, P. cymbalaria, P. cynthioides, P. debilis, P. dimorphophylla, P. eurycephala, P. fendleri, P. flettii, P. franciscana, P. ganderi, P. glabella, P. greenei, P. hartiana, P. hesperia, P. hyperborealis, P. indecora, P. ionophylla, P. layneae, P. macounii, P. malmstenii, P. millefolium, P. millelobata, P. multilobata, P. musiniensis, P. neomexicana, P. obovata, P. ogotorukensis, P. pauciflora, P. paupercula, P. plattensis, P. porteri, P. pseudaurea, P. quercetorum, P. sanguisorboides, P. schweinitziana, P. spellenbergii, P. streptanthifolia, P. subnuda, P. tampicana, P. texensis, P. tomentosa, P. tridenticulata, P. werneriifolia
Subordinate taxa
P. bolanderi var. bolanderi, P. bolanderi var. harfordii
Synonyms Senecio pauperculus, Senecio balsamitae, Senecio balsamitae var. firmifolius, Senecio balsamitae var. thomsoniensis, Senecio crawfordii, Senecio flavovirens, Senecio gaspensis, Senecio multnomensis, Senecio robbinsii var. subtomentosus, Senecio tweedyi Senecio bolanderi
Name authority (Michaux) Á. Löve & D. Löve: Bot. Not. 128: 520. (1976) (A. Gray) W. A. Weber & Á. Löve: Phytologia 49: 45. (1981)
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