Dilated Bog Orchid, Scentbottle, Scent Bottle Orchid, White Bog Orchid: Platanthera dilatata var. dilatata (Synonyms: Habenaria dilatata, Habenaria dilatata var. angustifolia, Habenaria dilatata var. dilatata, Limnorchis dilatata) - Flowers white. Spur about as long as lower lip and fairly thick.
Long-spurred Bog Orchid, Sierra Bog Orchid, White Bog Orchid: Platanthera dilatata var. leucostachys (Synonyms: Habenaria dilatata var. leuchostachys, Habenaria leucostachys, Limnorchis graminifolia, Limnorchis leucostachys, Limnorchis leucostachys var. leucostachys, Limnorchis leucostachys var. robusta, Platanthera leucostachys ) - Flowers white. Spur longer than lower lip and very thin.
Elegant Piperia, Elegant Rein Orchid, Elegant Rein-orchid, Hillside Rein Orchid, Hillside Rein-orchid, Long-spurred Rein Orchid: Platanthera elegans ssp. elegans (Synonyms: Habenaria elegans, Habenaria greenei, Piperia elegans ssp. elegans, Piperia maritima, Piperia multiflora) - Spur much longer than lower lip of flower. Sepals white with green central stripe. Spur curves downward along stem.
Denseflower Rein Orchid, Dense-flower Rein Orchid, Dense Orchid, Green-flowered Piperia: Platanthera elongata (Synonyms: Habenaria unalascensis ssp. elata, Habenaria unalascensis var. elata, Piperia elegans var. elata, Piperia elongata, Piperia lancifolia, Piperia longispica, Platanthera unalascensis ssp. elata) - Spur much longer than lower lip of flower. Sepals green, yellow-green or translucent. Spur curves downward along stem.
Slender Bog Orchid: Platanthera stricta (Synonyms: Habenaria hyperborea var. viridiflora, Habenaria saccata, Habenaria stricta, Limnorchis saccata, Limnorchis stricta, Limnorchis viridiflora, Platanthera convallariifolia, Platanthera dilatata var. gracilis, Platanthera hyperborea var. viridiflora, Platanthera saccata)- Flowers greeen. Spur shorter than lower lip and sac-like.
Royal Rein-orchid, Royal Rein Orchid, Suksdorf's Piperia, Suksdorf's Rein Orchid: Platanthera transversa (Synonyms: Habenaria elegans, Habenaria unalascensis var. elata, Piperia transversa) - Spur much longer than the lower lip of the flower. Sepals white with green central stripe. Spur held horizontal to the scape.
Alaska Rein Orchid, Alaskan Rein Orchid, Short-spurred Bog Orchid, Short-spurred Piperia, Slender-spire Orchid: Platanthera unalascensis (Synonyms: Habenaria unalascencis, Habenaria schischmareffiana, Piperia unalascensis, Platanthera cooperi, Spiranthes unalascensis) - Spur equal to or shorter than the lip. Sepals green, yellow-green or translucent.