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crested orange bog-orchid, crested yellow orchid

purple-petal bog orchid

Habit Plants 18–90 cm. Plants 24–80 cm.
Leaves

2–4, spreading to ascending, gradually reduced to bracts distally;

blade linear-lanceolate to lance-oblong, 5–21 × 1–3 cm.

few–several, abruptly diverging or sometimes ascending, scattered along stem;

blade oblong to ovate or lanceolate, 5.5–16(–28) × 1–4.5 cm.

Spikes

dense.

very lax to dense, flowers sometimes irregularly grouped in fascicles.

Flowers

resupinate, showy, orange;

dorsal sepal entire or sometimes emarginate;

lateral sepals spreading;

petals obovate to oblong-elliptic, margins fringed throughout to entire;

lip porrect, ovate to ovate-oblong, without basal thickening, 4–8 × 4–8 mm, margins deeply filiform-fringed;

spur slenderly cylindric (mouth triangular or keyhole-shaped), 4–10 mm;

rostellum lobes scarcely to strongly curved downward, rarely distally retrorse, digitate;

pollinaria with stalks curved downward;

pollinia remaining enclosed in anther sacs;

viscidia presented forward, nearly perpendicular to ± parallel to lip, orbiculate;

ovary slender, 7–13 mm.

resupinate, not showy, green to yellowish green, often suffused with blue or lip sometimes with red;

lateral sepals spreading to reflexed;

petals ovate- to lance-falcate, margins entire;

lip descending to somewhat reflexed or projecting, lanceolate to ovate, sometimes with prominent suborbiculate basal dilation, without basal thickening, 4–8 × 1.5–3 mm;

spur strongly clavate to scrotiform, 2–3 mm, apex obtuse;

rostellum lobes strongly diverging, very small, rounded, obscure;

pollinaria straight;

pollinia remaining enclosed in anther sacs;

viscidia orbiculate to oblong;

ovary rather slender to stout, mostly 5–9 mm.

2n

= 42.

= 42 [63].

Platanthera cristata

Platanthera purpurascens

Phenology Flowering (Jun–)Jul–Aug(–Sep). Flowering Jul–Aug.
Habitat Moist sandy and peaty meadows, marshes, prairies, pine savannas, wet wooded flats, seeping slopes, sphagnum bogs Stream banks, shores, ditches, fens, seeping slopes, roadsides, commonly in thickets, open woods
Elevation 0–800 m (0–2600 ft) 2500–3300 m (8200–10800 ft)
Distribution
from FNA
AL; AR; DE; FL; GA; LA; MA; MD; MS; NC; NJ; NY; PA; SC; TN; TX; VA
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CA; CO; NM; WY
[WildflowerSearch map]
Discussion

The rostellum lobes in Platanthera cristata normally are only slightly curved, presenting the viscidia in a generally forward position. Considerable variation is apparent, however, and sometimes a marked curvature similar to that in P. chapmanii is seen, apparently presenting the viscidia downward. These orientations are difficult to assess in distorted herbarium material, and the species is in need of further study. The triangular mouth of the spur of P. cristata is distinctive, however, and can aid in determination of confusing material (see also below and the discussion under 29. P. chapmanii).

Platanthera pallida P. M. Brown was recently proposed to accommodate two populations of pale-flowered plants on Long Island, New York. Their distinctive nature has long been apparent. In the field, pollination normally is rapid and the flowers senesce while small and yellowish, but in cultivation in the absence of pollinators, flowers remain open for an extended period during which the lips elongate markedly and the flowers fade to a dull white. Hence they suggest P. ×canbyi (Ames) Luer [P. blephariglottis × P. cristata], but they differ in their much shorter spurs.

Plants of Platanthera pallida were reported to differ from P. cristata in shorter spurs, entire dorsal sepals, and lateral sepal and lip orientation. The range of spur lengths in P. cristata, however, is much greater than specified and in fact includes the range of P. pallida. Dorsal sepals with entire margins are commonly seen also in P. cristata, and those of P. pallida may be deeply emarginate. Lateral sepal and lip orientation tend to differ in the two taxa, but the conditions typical of each taxon can be found in the other. The keyhole shaped orifice of the spur in P. pallida mentioned by Brown is a unique feature, but it is present in only a small percentage of individuals and completely intergrades to the triangular orifice of P. cristata. Furthermore, superficially similar pale-flowered plants from farther west on Long Island are more similar to typical P. cristata and hence possibly indicative of a cline. The plants described as P. pallida therefore appear to represent neither a distinct species nor are they merely hybrids; they seem to be partially stabilized introgression products and potentially useful subjects for evolutionary study.

Hybrids of Platanthera cristata with P. blephariglottis are P. ×canbyi (Ames) Luer and with P. ciliaris are P. ×channellii Folsom; until recently the latter was confused with P. chapmanii.

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

Flowers of Platanthera purpurascens are strongly semen scented, and their musty scent is markedly different than the sweet and spicy scents of other fragrant species.

In some areas this species hybridizes with Platanthera dilatata var. albiflora, producing sweetly fragant plants with lanceolate green lips. At the southern edge of its range, however, it often occurs with similar plants in the absence of another putative parent. The identity of these plants is uncertain. Their rather generalized morphology might mask polyphyletic origins.

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

Source FNA vol. 26, p. 568. FNA vol. 26, p. 560.
Parent taxa Orchidaceae > subfam. Orchidoideae > tribe Orchideae > subtribe Orchidinae > Platanthera Orchidaceae > subfam. Orchidoideae > tribe Orchideae > subtribe Orchidinae > Platanthera
Sibling taxa
P. aquilonis, P. blephariglottis, P. brevifolia, P. chapmanii, P. chorisiana, P. ciliaris, P. clavellata, P. convallariifolia, P. dilatata, P. flava, P. grandiflora, P. hookeri, P. huronensis, P. hyperborea, P. integra, P. integrilabia, P. lacera, P. leucophaea, P. limosa, P. macrophylla, P. nivea, P. obtusata, P. orbiculata, P. peramoena, P. praeclara, P. psycodes, P. purpurascens, P. sparsiflora, P. stricta, P. tipuloides, P. zothecina
P. aquilonis, P. blephariglottis, P. brevifolia, P. chapmanii, P. chorisiana, P. ciliaris, P. clavellata, P. convallariifolia, P. cristata, P. dilatata, P. flava, P. grandiflora, P. hookeri, P. huronensis, P. hyperborea, P. integra, P. integrilabia, P. lacera, P. leucophaea, P. limosa, P. macrophylla, P. nivea, P. obtusata, P. orbiculata, P. peramoena, P. praeclara, P. psycodes, P. sparsiflora, P. stricta, P. tipuloides, P. zothecina
Synonyms Orchis cristata, Habenaria cristata, P. pallida Limnorchis purpurascens, P. hyperborea var. purpurascens
Name authority (Michaux) Lindley: Gen. Sp. Orchid. Pl., 291. (1835) (Rydberg) Sheviak & W. F. Jennings: N. Amer. Native Orchid J. 3: 445. (1997)
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