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greater purple fringe bog-orchid, greater purple fringe orchid

Hooker's bog-orchid, Hooker's orchid

Habit Plants 27–120 cm. Plants 18–45 cm.
Leaves

2–6, wide-spreading and recurved to somewhat ascending, scattered along stem, gradually reduced to bracts distally;

blade lanceolate, elliptic, oblong-elliptic, or oblong-obovate, 13–24 × 2.5–9 cm.

2, in subequal basal pair, spreading-ascending or lying on ground;

bracts 0(–1, very rarely);

blade orbiculate, broadly elliptic, or obovate, 5–17 × 4–13 cm.

Spikes

lax to rather dense.

lax.

Flowers

resupinate, showy, lavender- to rose-purple, rarely white;

lateral sepals spreading to somewhat reflexed;

petals ovate, oblong, elliptic-oblong, or oblong-obovate, margins crenate to dentate-lacerate, sometimes nearly entire;

lip descending to somewhat porrect, deeply 3-lobed, without basal thickening, 10–25 × 14–26 mm, distal margins of lobes fringed, usually deeply, lateral lobes sometimes perpendicular to middle lobe, lateral lobes cuneate, often broadly so, middle lobe broadly cuneate-flabellate, often emarginate to 2-fid;

spur clavate, 15–35 mm;

rostellum lobes directed forward, spreading, angular;

pollinaria nearly straight;

pollinia remaining enclosed in anther sacs;

viscidia orbiculate;

ovary slender to stout, 12–25 mm.

resupinate, not showy;

calyx green;

corolla commonly yellowish green;

lateral sepals reflexed;

petals narrowly lanceolate-falcate, margins entire;

lip projecting to porrect, lanceolate to narrowly lance-rhombic, without basal thickening, 8–23 × 1–6 mm, margins entire;

spur slenderly conic, 11–27 mm;

rostellum lobes very wide-spreading, angular;

pollinaria nearly straight;

pollinia remaining enclosed in anther sacs;

viscidia suborbiculate;

ovary slender to rather stout, mostly 8–20 mm.

2n

= 42.

= 42.

Platanthera grandiflora

Platanthera hookeri

Phenology Flowering Jun–Aug. Flowering May–Aug.
Habitat Alluvial and swamp forests, stream banks, seeping slopes, marshes, sphagnum bog forests, mesic wooded slopes, old fields Dry to mesic coniferous and deciduous forest
Elevation 0–1800 m (0–5900 ft) mostly 0–500 m (mostly 0–1600 ft)
Distribution
from FNA
CT; MA; MD; ME; NC; NH; NJ; NY; OH; PA; RI; TN; VA; VT; WV; NB; NF; NS; ON; PE; QC
[WildflowerSearch map]
[BONAP county map]
from FNA
CT; IA; IL; IN; MA; ME; MI; MN; NH; NJ; NY; OH; PA; RI; VT; WI; MB; NB; NF; NS; ON; PE; QC
[WildflowerSearch map]
[BONAP county map]
Discussion

Platanthera grandiflora is known to hybridize with P. lacera in the northeasternmost portion of its range, where the species bloom simultaneously. The name P. ×keenanii P. M. Brown has recently been proposed for these hybrids, but the complex synonymy of this group dictates that types be checked for possible priority. See the discussion under P. lacera. A few specimens also suggest very rare hybridization with P. psycodes (W. P. Stoutamire 1974).

Rare white-flowered plants may be separated from 23. Platanthera leucophaea by the orientation of the pollinia.

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

Source FNA vol. 26, p. 565. FNA vol. 26, p. 555.
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. 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. 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
Synonyms Orchis grandiflora, Habenaria fimbriata, Habenaria psycodes var. grandiflora Habenaria hookeri, Habenaria hookeri var. abbreviata, P. hookeri var. abbreviata
Name authority (Bigelow) Lindley: Gen. Sp. Orchid. Pl., 294. (1835) (Torrey ex A. Gray) Lindley: Gen. Sp. Orchid. Pl., 286. (1835)
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