- Amerorchis rotundifolia — round-leaved orchis
- Aplectrum hyemale — puttyroot
- Arethusa bulbosa — dragon's mouth
- Calopogon tuberosus — tuberous grass-pink
- Calypso bulbosa — fairy slipper
- Cephalanthera austiniae — phantom orchid
- Coeloglossum viride — longbract green orchis
- Corallorhiza maculata — spotted coralroot
- Corallorhiza mertensiana — Merten's coralroot
- Corallorhiza odontorhiza — autumn coralroot
- Corallorhiza striata — striped coralroot
- Corallorhiza trifida — early coralroot
- Cypripedium acaule — pink lady's-slipper
- Cypripedium arietinum — ram's-head lady's-slipper
- Cypripedium candidum — small white lady's-slipper
- Cypripedium guttatum — spotted lady's-slipper
- Cypripedium montanum — mountain lady's-slipper
- Cypripedium parviflorum — American yellow lady's-slipper
- Cypripedium passerinum — sparrow's-egg lady's-slipper
- Cypripedium reginae — showy lady's-slipper
- Cypripedium x andrewsii — Andrews' lady's-slipper
- Cypripedium x columbianum — Columbian lady's-slipper
- Cypripedium x favillianum
- Cypripedium x landonii — Landon's lady's-slipper
- Dactylorhiza praetermissa — southern marsh orchid
- Epipactis gigantea — giant helleborine
- Galearis spectabilis — showy orchis
- Goodyera oblongifolia — giant rattlesnake-plantain
- Goodyera pubescens — downy rattlesnake-plantain
- Goodyera repens — dwarf rattlesnake-plantain
- Goodyera tesselata — checkered rattlesnake-plantain
- Isotria medeoloides — small whorled pogonia
- Isotria verticillata — large whorled pogonia
- Liparis liliifolia — large twayblade
- Liparis loeselii — Lösel's twayblade
- Malaxis brachypoda — white adder's-mouth
- Malaxis diphyllos — Aleutian adder's-mouth
- Malaxis paludosa — bog adder's-mouth
- Malaxis unifolia — green adder's-mouth
- Neottia auriculata — auricled twayblade
- Neottia australis — southern twayblade
- Neottia borealis — northern twayblade
- Neottia caurina — western twayblade
- Neottia convallarioides — broad-leaved twayblade
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- Neottia cordata — heartleaf twayblade
- Neottia x veltmanii — Veltman's twayblade
- Piperia candida — white piperia
- Piperia elegans — hillside rein orchid
- Piperia elongata — denseflower rein orchid
- Piperia transversa — royal rein orchid
- Piperia unalascensis — Alaska rein orchid
- Platanthera albida — vanilla-scent bog orchid
- Platanthera aquilonis
- Platanthera blephariglottis — white-fringe orchis
- Platanthera chorisiana — Choriso bog orchid
- Platanthera clavellata — small green woodland orchid
- Platanthera dilatata — leafy white orchis
- Platanthera flava — southern rein orchid
- Platanthera grandiflora — large purple-fringe orchis
- Platanthera hookeri — Hooker's orchis
- Platanthera hyperborea — leafy northern green orchid
- Platanthera lacera — green-fringe orchis
- Platanthera leucophaea — eastern prairie white-fringed orchid
- Platanthera leucostachys — Bog rein orchid, scentbottle
- Platanthera obtusata — small northern bog orchid
- Platanthera orbiculata — large roundleaf orchid
- Platanthera praeclara — western prairie white-fringed orchid
- Platanthera psycodes — small purple-fringe orchis
- Platanthera stricta — slender bog orchid
- Platanthera x andrewsii — Andrews' platanthera
- Platanthera x hollandiae — Holland's platanthera
- Platanthera x keenanii — Keenan's platanthera
- Platanthera x media
- Platanthera x reznicekii — Reznicek's platanthera
- Platanthera x vossii — Voss' platanthera
- Pogonia ophioglossoides — rose pogonia
- Spiranthes casei — Case's ladies'-tresses
- Spiranthes cernua — nodding ladies'-tresses
- Spiranthes lacera — southern slender ladies'-tresses
- Spiranthes lucida — shining ladies'-tresses
- Spiranthes magnicamporum — Great Plains ladies'-tresses
- Spiranthes ochroleuca — yellow nodding ladies'-tresses
- Spiranthes ovalis — lesser ladies'-tresses
- Spiranthes romanzoffiana — hooded ladies'-tresses
- Spiranthes x intermedia
- Spiranthes x simpsonii — Simpson's ladies'-tresses
- Triphora trianthophora — nodding pogonia
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