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dotted saxifrage, heartleaf saxifrage, Nelson's saxifrage, saxifrage

eastern swamp saxifrage, marsh, marsh saxifrage, Pennsylvania, Pennsylvania saxifrage, swamp saxifrage, swamp small-flower-saxifrage

Habit Plants solitary or tufted, with bulbils on branched caudices, rhizomatous. Plants solitary or in groups, with thick, fleshy rhizomes.
Leaves

basal;

petiole rounded, 3–30 cm;

blade reniform to round, 2–9 cm, thin or slightly fleshy, sometimes thick and fleshy, base cordate, margins deeply crenate, eciliate or sparsely short glandular-ciliate, surfaces glabrous or ± hairy.

basal;

petiole indistinct, flattened, 3–10 cm;

blade linear or elliptic to ovate, 6–25 cm, fleshy, base attenuate, margins entire or subentire, ciliate, surfaces usually densely short-hairy, often tangled brown-hairy along proximal midveins.

Inflorescences

10+-flowered, ± open, lax to congested, conic, sometimes also glomerate thyrses, 10–35 cm, tangled-hairy (pilose-arachnoid) at least distally, sometimes also purple- or brown-tipped stipitate-glandular.

(30–)50+-flowered, open, often lax thyrses, 25–125 cm, purple-tipped stipitate-glandular.

Flowers

sepals reflexed, ± ovate;

petals white to pinkish, rarely orange-spotted, ovate to oblong, narrowly to broadly clawed, 2.5–4.5 mm, longer than sepals;

filaments distinctly club-shaped;

pistils connate 1/2–3/4 their lengths;

ovary superior (to 1/3 adnate to hypanthium).

sepals reflexed, triangular to ovate;

petals white to cream or rarely purple, not spotted, linear to narrowly elliptic, not clawed or slightly clawed, 2–3 mm, longer than sepals;

filaments linear, flattened;

pistils connate to 1/2 their lengths;

ovary 1/2+ inferior, appearing superior in fruit.

Capsules

green to yellow and purplish tinged to dark purple, valvate.

green, folliclelike.

2n

= 56, 84, 112.

Micranthes nelsoniana

Micranthes pensylvanica

Phenology Flowering spring.
Habitat Marshy meadows, mucky seepages in woods, swamp forests, montane bogs and seeps
Elevation 100-1400 m (300-4600 ft)
Distribution
from FNA
AK; OR; WA; AB; BC; NT; NU; YT; Europe (ne Russia); Asia
[WildflowerSearch map]
[BONAP county map]
from FNA
CT; DE; IA; IL; IN; KY; MA; MD; ME; MI; MN; MO; NC; NH; NJ; NY; OH; PA; RI; TN; VA; VT; WI; WV; MB; ON; SK
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 6 (5 in the flora).

Although sometimes reported for North America, Saxifraga nelsoniana var. aestivalis (Fischer & C. A. Meyer) H. Ohba (S. aestivalis Fischer & C. A. Meyer) is found only in Eurasia.

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

Purple-petalled populations of Micranthes pensylvanica have been known as Saxifraga purpuripetala and are found in Maine, New York, Pennsylvania, and Vermont.

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

Key
1. Inflorescences purple- or brown-tipped stipitate- glandular.
var. nelsoniana
1. Inflorescences tangled-hairy
→ 2
2. Leaf blade margins 9-12-toothed; capsules 6-12 mm; mostly Queen Charlotte Islands, adjacent coastal British Columbia.
var. carlottae
2. Leaf blade margins 12-18-toothed; capsules 3-8 mm; Oregon to Alaska and nw Canada
→ 3
3. Inflorescences somewhat lax, hairs appressed; Coast Ranges and Cascades, British Columbia, Oregon, Washington.
var. cascadensis
3. Inflorescences congested, hairs ascending; nw Canada, Alaska
→ 4
4. Leaf blades thick, fleshy; pistils connate most of their lengths; Aleutian Islands, Alaska.
var. insularis
4. Leaf blades thin, not fleshy; pistils connate to 3/4 their lengths; nw Canada, Alaska.
var. porsildiana
Source FNA vol. 8, p. 54. FNA vol. 8, p. 67.
Parent taxa Saxifragaceae > Micranthes Saxifragaceae > Micranthes
Sibling taxa
M. apetala, M. aprica, M. bryophora, M. californica, M. calycina, M. careyana, M. caroliniana, M. eriophora, M. ferruginea, M. foliolosa, M. fragosa, M. gaspensis, M. gormanii, M. hieraciifolia, M. hitchcockiana, M. howellii, M. idahoensis, M. integrifolia, M. lyallii, M. marshallii, M. micranthidifolia, M. nidifica, M. nivalis, M. nudicaulis, M. occidentalis, M. odontoloma, M. oregana, M. palmeri, M. pensylvanica, M. petiolaris, M. razshivinii, M. reflexa, M. rhomboidea, M. rufidula, M. spicata, M. stellaris, M. subapetala, M. tempestiva, M. tenuis, M. texana, M. tischii, M. tolmiei, M. unalaschcensis, M. virginiensis
M. apetala, M. aprica, M. bryophora, M. californica, M. calycina, M. careyana, M. caroliniana, M. eriophora, M. ferruginea, M. foliolosa, M. fragosa, M. gaspensis, M. gormanii, M. hieraciifolia, M. hitchcockiana, M. howellii, M. idahoensis, M. integrifolia, M. lyallii, M. marshallii, M. micranthidifolia, M. nelsoniana, M. nidifica, M. nivalis, M. nudicaulis, M. occidentalis, M. odontoloma, M. oregana, M. palmeri, M. petiolaris, M. razshivinii, M. reflexa, M. rhomboidea, M. rufidula, M. spicata, M. stellaris, M. subapetala, M. tempestiva, M. tenuis, M. texana, M. tischii, M. tolmiei, M. unalaschcensis, M. virginiensis
Subordinate taxa
M. nelsoniana var. carlottae, M. nelsoniana var. cascadensis, M. nelsoniana var. insularis, M. nelsoniana var. nelsoniana, M. nelsoniana var. porsildiana
Synonyms Saxifraga nelsoniana, Saxifraga punctata subsp. nelsoniana, Saxifraga punctata var. nelsoniana Saxifraga pensylvanica, M. pensylvanica var. purpuripetala, Saxifraga forbesii, Saxifraga pensylvanica var. forbesii, Saxifraga pensylvanica subsp. interior, Saxifraga pensylvanica var. purpuripetala, Saxifraga pensylvanica subsp. tenuirostrata, Saxifraga purpuripetala
Name authority (D. Don) Small: in N. L. Britton et al., N. Amer. Fl. 22: 147. 1905 , (Linnaeus) Haworth: Saxifrag. Enum., 45. (1821)
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