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blunt-leaf bog-orchid, blunt-leaf rein-orchid, blunt-leafed rein orchid, bluntleaf orchid, northern small bog orchid, one-leaf rein-orchid, small northern bog-orchid

northern tubercled bog-orchid, palegreen orchid

Habit Plants 5.5–35 cm. Plants 13–65 cm.
Leaves

1(–2, rarely), spreading-ascending on base of stem;

bracts 0(–1, rarely);

blade linear-oblanceolate, elliptic, or broadly obovate, 3.5–15 × 0.8–5 cm.

(1–)2–3(–4), spreading to ascending, gradually to rather abruptly reduced to bracts distally;

blade lanceolate to elliptic-oblong, 5–35 × 1–7 cm.

Spikes

lax.

lax to dense.

Flowers

resupinate, not showy, greenish white to yellowish green;

corolla commonly whiter than calyx;

lateral sepals reflexed;

petals rhombic, lanceolate-falcate, margins entire;

lip descending, linear, narrowly lance-rhombic, or linear-hastate, with median basal thickening, unlobed, 2.5–8(–10) × less than 1–2 mm, margins entire;

spur slenderly conic, 3–8(–10) mm;

rostellum lobes directed forward, wide-spreading, rounded-angular;

pollinaria straight;

pollinia remaining enclosed in anther sacs;

viscidia orbiculate;

ovary rather slender to stout, mostly 3–10 mm.

resupinate, inconspicuous, yellowish green;

lateral sepals porrect to reflexed;

petals oblong-orbiculate to ovate, apex somewhat crenulate;

lip descending to commonly reflexed, 2–6 × 1.8–5 mm, base auriculate, with prominent central tubercle, distal margin entire to slightly crenulate;

spur cylindric to strongly clavate, 4–8(–11) mm, apex rarely 2-lobed;

rostellum lobes mostly parallel to slightly diverging, directed downward, minute, obscure;

pollinia remaining enclosed in anther sacs;

viscidia mostly quadrangular, oblong-quadrangular, orbiculate, or broadly asymmetric, commonly canaliculate to nearly cylindric and difficult to assess;

ovary rather slender to stout, mostly 8–10 × 2 mm.

2n

= 42, 63 (American, as Habenaria obtusata), 126 (Eurasian, as Habenaria obtusata).

Platanthera obtusata

Platanthera flava

Phenology Flowering Jun–Aug.
Habitat Mesic to wet coniferous forest, forested fens, sphagnum bogs, stream banks, tundra, moist roadsides
Elevation 0–3500 m (0–11500 ft)
Distribution
from FNA
AK; CO; ID; MA; ME; MI; MN; MT; NH; NY; OR; UT; VT; WA; WI; WY; AB; BC; MB; NB; NL; NS; NT; NU; ON; PE; QC; SK; YT; Eurasia [Platanthera obtusata subsp oligantha]
[WildflowerSearch map]
[BONAP county map]
from USDA
e North America
[WildflowerSearch map]
[BONAP county map]
Discussion

The rare Eurasian Platanthera obtusata subsp. oligantha (Turczaninow) Hultén differs from the North American subsp. obtusata in its smaller dimensions and rhombic-lanceolate lip. It is also said to be densely few-flowered, although some Siberian material is comparable to American plants. Supposedly intermediate plants are reported from Alaska, and much material from that area is reduced in stature and with smaller flowers than typical of American plants. In most cases, however, lips are relatively slender, and the plants seem merely to be stunted by their environment. One or two collections from the Alaskan Peninsula and Aleutians, however, seem entirely referable to subsp. oligantha with dense, few-flowered inflorescences of very small flowers with rhombic-lanceolate lips and shorter curved spurs. Eurasian plants are reported to be hexaploid or perhaps sometimes triploid, and if the apparent ploidy differences delimit the taxa, then it should be possible to unequivocally identify Alaskan plants.

(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.)

Key
1. Lip (excluding auricles) subquadrangular, suborbiculate, or broadly ovate, often emarginate; inflorescences usually rather lax, slender (this enhanced by floral bracts mostly shorter than flowers).
var. flava
1. Lip (excluding auricles) oblong, usually obtuse, (rarely triangular, acute); inflorescences usually rather dense, stout (this emphasized by floral bracts usually long, often greatly exceeding flowers).
var. herbiola
Source FNA vol. 26, p. 556. FNA vol. 26, p. 563.
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. 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. 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. 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
Subordinate taxa
P. flava var. flava, P. flava var. herbiola
Synonyms Orchis obtusata, Habenaria obtusata, Habenaria obtusata var. collectanea Orchis flava, Habenaria flava, Perularia scutellata
Name authority (Banks ex Pursh) Lindley: Gen. Sp. Orchid. Pl., 284. (1835) (Linnaeus) Lindley: Gen. Sp. Orchid. Pl., 293. (1835)
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