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stiff-leaf goldenrod

Riddell's goldenrod

Habit Plants 30–150 cm; caudices branching, woody. Plants 40–100 cm; caudices branching; vascular bundles and petiole bases marcescent (attached to old stems for more than a season).
Stems

1–10+, erect, stout, hairy.

1–10+, erect, glabrous.

Leaves

basal and proximal cauline usually present at flowering, abruptly narrowed to long petioles, blades ovate to rhombic, 80–200 × 24–50 mm, firm, flat, margins entire to crenate, sometimes undulate, apices obtuse to acute, faces densely hairy;

mid to distal cauline sessile, blades ovate, 30–50 × 15–17 mm, stiff, greatly reduced distally, margins entire or finely serrate, sometimes undulate, apices acute to obtuse.

basal and proximal cauline usually withering by flowering (other rosettes may be present), tapering to long, winged petioles, blades often recurved, linear- lanceolate or -oblanceolate, 100–240 × 8–16 mm, folded along midrib (V-shaped in cross section), bases usually with (2–)3–8 prominent lateral nerves, apices acute to obtuse, faces glabrous;

mid to distal cauline sessile, blades recurved, linear-lanceolate, 50–70 × 8–11 mm, reduced distally, folded, bases with prominent lateral nerves.

Peduncles

3–15 mm, strigillose-canescent, bracteoles 1–3, linear-lanceolate.

2.8–4 mm, moderately short-hispido-strigose, lanceolate bracteoles 0–1.

Involucres

campanulate, 6–8 mm.

narrowly campanulate, 4.5–6 mm.

Ray florets

6–13;

laminae 1.4–5.4 × 1.2–1.9 mm.

7–9;

laminae 4.5–5.5 × 0.4–0.5 mm.

Disc florets

14–35;

corollas 4.3–6.1 mm, lobes 0.6–1.1 mm.

6–10;

corollas 4.5–5.2 mm, lobes 0.7–1.8 mm.

Phyllaries

in 3–4 series, unequal, oblong, conspicuously striate (3–5 pronounced nerves), obtuse.

(14–18) in 3–4 series, unequal, obtuse, broad, striations weak, obtuse to rounded, glabrous.

Heads

9–190, in corymbiform arrays, compact or branches long and spreading, densely hairy throughout.

30–450 in corymbiform to somewhat paniculiform with rounded corymbiform branches (robust plants) arrays, branches and peduncles strigillose.

Cypselae

(obconic) 0.8–1.7 mm (ribbed), glabrous or strigillose apically;

pappi 3–4 mm.

1.5–2.2 mm, glabrous;

pappi 3.5–4 mm (apically clavate).

2n

= 18.

Solidago rigida

Solidago riddellii

Phenology Flowering Sep–Oct.
Habitat Wet prairielike sites and marshy ground
Elevation 100–400 m (300–1300 ft)
Distribution
from FNA
AL; AR; CO; CT; DE; GA; IA; IL; IN; KS; KY; LA; MA; MD; MI; MO; MS; MT; NC; ND; NE; NJ; NM; NY; OH; OK; PA; RI; SC; SD; TN; TX; VA; WI; WV; WY; AB; MB; ON; SK
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from FNA
IL; IN; MI; MN; MO; OH; WI; MB; ON
[WildflowerSearch map]
[BONAP county map]
Discussion

Subspecies 3 (3 in the flora).

Solidago rigida is divided into three subspecies with distinct morphologies and partially overlapping ranges. Intermediates occur between the subspecies in areas of sympatry.

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

Key
1. Outer phyllaries glabrous; leaves and stems glabrous or ± hispid
subsp. glabrata
1. Outer phyllaries strigillose; leaves and stems moderately to densely hispid or strigose
→ 2
2. Inner phyllaries glabrate to sparsely strigillose, oblong and rounded; plants robust (60–150 cm); arrays loose, open; leaves and stems coarsely hispid (fewer than 50 hairs/mm 2)
subsp. rigida
2. Inner phyllaries conspicuously strigillose, often linear; plants usually short (30–70 cm), sometimes taller; arrays compact; leaves and stems finely and densely hispido-strigose (more than 50 hairs/mm 2)
subsp. humilis
Source FNA vol. 20, p. 163. FNA vol. 20, p. 165.
Parent taxa Asteraceae > tribe Astereae > Solidago > sect. Ptarmicoidei Asteraceae > tribe Astereae > Solidago > sect. Ptarmicoidei
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. ptarmicoides, S. puberula, S. pulchra, S. radula, S. riddellii, 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. 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
Subordinate taxa
S. rigida subsp. glabrata, S. rigida subsp. humilis, S. rigida subsp. rigida
Synonyms Aster rigidus, Oligoneuron rigidum Aster riddellii, Oligoneuron riddellii, S. amplexicaulis
Name authority Linnaeus: Sp. Pl. 2: 880. (1753) Frank: W. J. Med. Phys. Sci. 8: 499. (1835)
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