|  | Platanthera: Answers
    to key questions in Lilies, Irises & Orchids of Saskatchewan by
    Vernon L. Harms and Anna L. Leighton leading to this genus. The answers
    are in the order you would normally work through the key. 
     
      |  | Plants
        green, with at least some green leaf-blades, these sometimes early
        withering or late developing; flowering stems green (pale pink to
        purplish-red in Calypso bulbosa), bearing sheathing bracts in
        some species; rootstocks not coral-like; capsules spreading to erect
        (occasionally drooping when old); NOT [Plants non-green saprophytes
        lacking leaf-blades; flowering stems yellowish to purplish-red or brown
        (pale greenish-yellow in C. trifid), bearing sheathing bracts;
        rhizomes rootless, coral-like in their branching; capsules drooping] |  |  | Flowers 3
        or more in a spike-like inflorescence, small, often inconspicuous; lip
        usually less than 1 cm long, but if longer, neither inflated nor broad
        and flat; NOT [Flowers 1 to 2 per stalk (occasionally more in Cypripedium
        reginae and C. montanum), large, showy; lip 1 cm long or
        longer, either inflated or broad and flat] |  |  | Lip
        spurred (spur short and bag-like in Coeloglossum  viride);
        NOT [Lip not spurred] |  |  | Lip
        yellowish-green (often tinged with red  in Coeloglossum) or
        white, unmarked, narrower, tongue- or strap-shaped, lacking lateral 
        lobes; flower stems leafy (except in Platanthera obtusata which
        has a single leaf at base of stem, and Platanthera orbiculata,
        which has two leaves, both basal) arising from clusters of thick roots;
        NOT [Lip white with roseate spots, ovate in outline with a pair of
        protruding lateral lobes near base; terminal lobe flared and usually
        notched; flower stems naked with a single leaf present at base of stalk
        and arising from rhizomes with slender roots] |  |  | Lip not
        toothed at tip, about the same length as spur; stems leafy or leafless;
        floral bracts shorter; flowers greenish, greenish-white, or white;
        clusters of roots not palmately arranged; NOT [Lip 2 (3)-toothed at tip,
        much longer than the inconspicuous pouch-like spur; stems with up to 5 
        leaves; floral bracts prominent throughout inflorescence, elongated to
        2-4 times flower length on raceme lower portions; flowers greenish to
        yellowish-green; clusters of roots palmately-arranged] |    |