Spiranthes ochroleuca |
Spiranthes casei |
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yellow ladies'-tresses, yellow nodding ladies'-tresses, yellow nodding lady's tresses |
Case's ladies'-tresses, Case's lady's tresses, spiranthe de Case |
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Habit | Plants 10–55 cm. | Plants 7–44 cm. | ||||
Roots | few, horizontally spreading, slender, mostly to 0.4 cm diam. |
few–several, descending, slender to somewhat tuberously thickened, mostly to 0.5 cm diam. |
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Leaves | persisting through anthesis, basal, sometimes on basal portion of stem, spreading, linear-oblanceolate to narrowly elliptic, to 21 × 2 cm. |
persisting through anthesis, basal and on proximal portion of stem, ascending to spreading, ovate-lanceolate to linear-lanceolate to oblanceolate, to 20 × 2 cm. |
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Spikes | rather loosely to very tightly spiraled, 3–4 flowers per cycle of spiral, occasionally 5 or more in very loose spiral; rachis moderately pubescent, some trichomes capitate, glands obviously stalked. |
loosely spiraled, usually 5 or more flowers per cycle of spiral; rachis moderately to densely pubescent, some trichomes capitate, glands obviously stalked. |
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Flowers | ochroleucous, ivory, creamy, yellowish, or greenish white, ascending, urceolate to somewhat gaping, claw of lip at pronounced (20–60°) angle to lamina, base cuneate, appearing strongly inflated; sepals distinct to base, 6–14 mm; lateral sepals appressed to petals and lip, straight, separated from dorsal sepal by mostly 0.7–1 mm; petals linear to linear-oblong, 6–13 mm, apex acute to obtuse; lip often more yellow centrally, oblong to ovate, 7–12 × 4–7 mm, margins crenulate, glabrous; veins several, branches parallel; basal calli incurved, prominent, very rarely conic, 1–2 mm; viscidia linear; ovary 3–7 mm. |
ivory to yellowish white or greenish cream, strongly nodding, curved downward throughout lengths, scarcely gaping, urceolate-tubular; sepals distinct to base, 5.2–8 mm; lateral sepals slightly spreading, apex straight; petals creamy white to greenish white, ovate-elliptic to obovate, 3.9–7.6 mm, apex obtuse; lip often darker centrally, 4.1–8 × 3.2–5.1 mm, glabrous; veins several, branches parallel; basal calli incurved, prominent, 0.7–1.1 mm; viscidia linear to linear-lanceolate; ovary 4–7 mm. |
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Seeds | monoembryonic. |
partly or wholly polyembryonic. |
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2n | = 30. |
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Spiranthes ochroleuca |
Spiranthes casei |
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Phenology | Flowering Aug–Nov. | |||||
Habitat | Dry to mesic open woodland, thickets, meadows, barrens, ledges, outcrops, banks and roadsides, old fields | |||||
Elevation | 0–1700 m (0–5600 ft) | |||||
Distribution |
CT; IN; KY; MA; MD; ME; MI; NC; NH; NJ; NY; OH; PA; RI; SC; TN; VA; VT; WV; NB; NS; ON; PE
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e North America; c North America along Canadian and Unites States border
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Discussion | While leaves of Spiranthes ochroleuca are usually present at anthesis, in prairie populations they are commonly absent. Spiranthes ×steigeri was described as a hybrid of S. cernua and S. romanzoffiana, but additional study (P. M. Catling 1984) has shown the plants to be referable to S. ochroleuca. See notes on gene flow and apomixis under 14. Spiranthes cernua. Hybrids of Spiranthes ochroleuca with S. casei are known as S. ×borealis P. M. Brown. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Varieties 2 (2 in the flora). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 26, p. 539. | FNA vol. 26, p. 541. | ||||
Parent taxa | Orchidaceae > subfam. Orchidoideae > tribe Cranichideae > subtribe Spiranthinae > Spiranthes | Orchidaceae > subfam. Orchidoideae > tribe Cranichideae > subtribe Spiranthinae > Spiranthes | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Gyrostachys ochroleuca, S. cernua var. ochroleuca, S. ×steigeri | |||||
Name authority | (Rydberg) Rydberg: Fl. Plains N. Amer., 241. (1932) | Catling & Cruise: Rhodora 76: 527, figs. 1–4. (1974) | ||||
Web links |