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prairie goldenrod, upland white aster, verge-d'or faux-ptarmica, white flat-top goldenrod

noble goldenrod, showy goldenrod

Habit Plants 10–40 cm; caudices branching; vascular bundles and petiole bases marcescent (attached to old stems for more than a season). Plants (30–)50–200 cm; caudices stout, woody.
Stems

1–20+, erect, slender, glabrous proximally, hispid distally.

1(–5), erect, glabrous proximally to strigillose in arrays.

Leaves

basal and proximal cauline persistent, subpetiolate to sessile, blades sometimes 3-nerved, linear to linear-lanceolate, 60–100 × 7–10 mm, stiff, flat, margins entire or subentire, faces glabrous or sparsely hairy;

mid to distal cauline sessile, blades linear oblanceolate to linear, 20–40 × 3–5 mm, reduced distally, margins entire.

basal and proximal cauline (sometimes withering by flowering) tapering to winged petioles, blades lanceolate to ovate-elliptic, 50–300 (including petiole) × 12–80 mm (sometimes firm), margins sharply serrate to crenate or entire, faces glabrate to sparsely strigillose;

mid to distal cauline sessile, blades narrowly ovate to lanceolate or elliptic, 25–90 × 5–30 mm, gradually reduced distally, margins serrulate to entire (distally), ciliate, faces glabrous or sparsely scabroso-strigose.

Peduncles

29–36.5 mm, strigillose;

bracteoles linear.

1.5–3 mm, sparsely to moderately scabroso-strigillose;

bracteoles linear, grading into phyllaries, scattered along peduncles, clustered near heads.

Involucres

5–6 mm.

narrowly campanulate, 4–6.5 mm.

Ray florets

10–20, usually white, rarely pale yellow (conspicuous);

laminae 7–7.3 × 1.4–1.6 mm.

(2–)3–7(–9);

laminae 3–4 × 0.5–1 mm.

Disc florets

30–36;

corollas 3.8–4.1 mm, lobes 0.5–0.7 mm.

6–16;

corollas 2.5–4 mm, lobes 0.5–1.2 mm.

Phyllaries

in 4–5 series, usually prominently 1-nerved, linear, strongly unequal, outer acute, inner acute to obtuse, glabrous.

in 3–4 series, appressed, strongly unequal, outer ovate, mid and inner lanceolate, (midnerves often raised and thick) apices acute to obtuse or rounded, glabrous.

Heads

1–25(–50), in corymbiform arrays.

15–300+, not secund, in usually dense, sometimes open, elongate, paniculiform to thyrsiform arrays, (5–)10–45 × (2–)3–7(–12) cm;

branches strongly ascending, often racemiform.

Cypselae

(obconic) 1–1.5 mm (ribbed), glabrous;

pappi 3.4–4 mm (apically clavate).

(narrowly obconic) 1.6–2.5 mm, glabrous;

pappi 3–4.5 mm.

2n

= 18.

Solidago ptarmicoides

Solidago speciosa

Phenology Flowering Jul–Oct.
Habitat Dry, sandy, usually calcareous soils, cracks in rocks, limestone pavements, rocky outcrops, grassy slopes, prairies
Elevation 0–1500 m (0–4900 ft)
Distribution
from FNA
CO; CT; IA; IL; IN; MI; MN; MO; MT; NH; NY; OH; OK; SC; SD; VT; WI; WY; MB; ON; QC; SK
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; CO; CT; DE; GA; IA; IL; IN; KS; KY; LA; MA; MD; MI; MN; MO; MS; NC; ND; NE; NJ; NM; NY; OH; OK; RI; SC; SD; TN; TX; VA; VT; WI; WV; WY; ON
[WildflowerSearch map]
[BONAP county map]
Discussion

L. Brouillet and J. C. Semple (1981) summarized the morphologic, chemical, cytological, and hybridization data on Solidago ptarmicoides and concluded that, except for the white rays, it is a typical member of sect. Ptarmicoidei. The species hybridizes with S. rigida, S. ohioensis, S. riddellii, and perhaps other goldenrods. It is not known to hybridize with any species of aster (regardless of genus); the supposed Aster × Solidago hybrids are the basis of all reports of intergeneric hybrids in the literature. Horticultural hybrids involving S. ptarmicoides and other Solidago species have been treated as S. ×luteus (M. L. Green ex Dress) Brouillet & Semple (×Solidaster luteus M. L. Green ex Dress). Solidago ×bernardii B. Boivin [Oligoneuron ×bernardii (B. Boivin) G. L. Nesom] is the formal name applied to S. ptarmicoides × S. riddellii hybrids; those have cream rays. Solidago ×lutescens (Lindley ex de Candolle) B. Boivin [Diplopappus lutescens Lindley ex de Candolle; D. albus var. lutescens (Lindley ex de Candolle) Hooker ex Torrey & A. Gray; Aster lutescens (Lindley ex de Candolle) Hooker ex Torrey & A. Gray; A. ptarmicoides var. lutescens (Lindley ex de Candolle) A. Gray; Oligoneuron ×lutescens (Lindley ex de Candolle) G. L. Nesom] applies to hybrids between S. ptarmicoides and S. rigida or S. riddellii from the prairies; these also have cream colored rays.

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

Subspecies 2 (2 in the flora).

Solidago speciosa occurs scattered throughout its range, often in small populations. Five races have been acknowledged; only three varieties appear to warrant recognition. The species is divided into two nearly allopatric subspecies. The typical subspecies includes two varieties that are sometimes difficult to distinguish and considerably overlap in their ranges. The differences in size and number of leaves and persistence of the proximal cauline leaves may be caused in part by growing conditions.

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

Key
1. Leaves pale green, somewhat glaucous; plants 30–80 cm; e Colorado, extreme w Oklahoma, and adjacent New Mexico, disjunct in Black Hills (S. speciosa subsp. pallida)
var. pallida
1. Leaves usually dark green, not glaucous; plants usually 80–200 cm; e deciduous forest onto e prairies and oak savannas (S. speciosa subsp. speciosa)
→ 2
2. Basal leaves usually present at flowering, (20–) 28–55 mm wide, often coarsely serrate; mid cauline leaves (10–)20–28 mm wide, not crowded, not stiff, not scabrous; e UnitedStates
var. speciosa
2. Basal leaves persisting or not to flowering, 8–20 mm wide, often entire or shallowly serrate; mid cauline leaves 4–15(–20) mm wide, often crowded, usually stiff, often somewhat scabrous; w portions of deciduous forest and adjacent prairies, glade habitats further east
var. rigidiuscula
Source FNA vol. 20, p. 164. FNA vol. 20, p. 123.
Parent taxa Asteraceae > tribe Astereae > Solidago > sect. Ptarmicoidei Asteraceae > tribe Astereae > Solidago > sect. Solidago > subsect. Squarrosae
Sibling taxa
S. albopilosa, S. altiplanities, S. altissima, S. arenicola, S. arguta, S. auriculata, S. bicolor, S. brachyphylla, S. buckleyi, S. caesia, S. canadensis, S. confinis, S. curtisii, S. delicatula, S. drummondii, S. elongata, S. erecta, S. faucibus, S. fistulosa, S. flexicaulis, S. gattingeri, S. gigantea, S. glomerata, S. guiradonis, S. hispida, S. houghtonii, S. juliae, S. juncea, S. kralii, S. lancifolia, S. latissimifolia, S. leavenworthii, S. leiocarpa, S. lepida, S. ludoviciana, S. macrophylla, S. missouriensis, S. mollis, S. multiradiata, S. nana, S. nemoralis, S. nitida, S. odora, S. ohioensis, S. ouachitensis, S. patula, S. petiolaris, S. pinetorum, S. plumosa, S. puberula, S. pulchra, S. radula, S. riddellii, S. rigida, S. roanensis, S. rugosa, S. rupestris, S. sciaphila, S. sempervirens, S. shortii, S. simplex, S. spathulata, S. speciosa, S. spectabilis, S. sphacelata, S. spithamaea, S. squarrosa, S. stricta, S. tarda, S. tortifolia, S. uliginosa, S. ulmifolia, S. velutina, S. verna, S. villosicarpa, S. wrightii
S. albopilosa, S. altiplanities, S. altissima, S. arenicola, S. arguta, S. auriculata, S. bicolor, S. brachyphylla, S. buckleyi, S. caesia, S. canadensis, S. confinis, S. curtisii, S. delicatula, S. drummondii, S. elongata, S. erecta, S. faucibus, S. fistulosa, S. flexicaulis, S. gattingeri, S. gigantea, S. glomerata, S. guiradonis, S. hispida, S. houghtonii, S. juliae, S. juncea, S. kralii, S. lancifolia, S. latissimifolia, S. leavenworthii, S. leiocarpa, S. lepida, S. ludoviciana, S. macrophylla, S. missouriensis, S. mollis, S. multiradiata, S. nana, S. nemoralis, S. nitida, S. odora, S. ohioensis, S. ouachitensis, S. patula, S. petiolaris, S. pinetorum, S. plumosa, S. ptarmicoides, S. puberula, S. pulchra, S. radula, S. riddellii, S. rigida, S. roanensis, S. rugosa, S. rupestris, S. sciaphila, S. sempervirens, S. shortii, S. simplex, S. spathulata, S. spectabilis, S. sphacelata, S. spithamaea, S. squarrosa, S. stricta, S. tarda, S. tortifolia, S. uliginosa, S. ulmifolia, S. velutina, S. verna, S. villosicarpa, S. wrightii
Subordinate taxa
S. speciosa var. pallida, S. speciosa var. rigidiuscula, S. speciosa var. speciosa
Synonyms Aster ptarmicoides, Diplopappus albus, Diplopappus ptarmicoides, Doellingeria ptarmicoides, Eucephalus albus, Heleastrum album, Inula alba, Oligoneuron album, S. asteroides, Unamia alba, Unamia ptarmicoides Aster speciosus
Name authority (Torrey & A. Gray) B. Boivin: Phytologia 23: 21. (1972) Nuttall: Gen. N. Amer. Pl. 2: 160. (1818)
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