Ontario Wildflowers website

Ladies' Tresses

Summary of Key Identification Points of Ladies' Tresses

This page covers the key identification featires of Ladies' Tresses.

Ladies' Tresses are notoriously difficult to tell apart. The following features for each species have been compiled from various orchid books and botanists, along with my own observations.

Nodding Ladies' Tresses (Spiranthes cernua)

Hooded Ladies' Tresses (Spiranthes romanzoffiana)

Great Plains Ladies' Tresses (Spiranthes magnicamporum)

  • rare in Ontario
  • flowers: large
  • flowers: fragrant: almond and vanilla scent
  • flowers: multi-ranked
  • flowers: very late blooming: September-October

Wide-leaved Ladies' Tresses (Spiranthes lucida)

  • flowers: yellow throat, white edges
  • flowers: blooms early: the first of the Ladies' Tresses to bloom
  • flowers: multi-ranked
  • leaves: broad shining leaves
  • habitat: wet gravelly places

Case's Ladies' Tresses (Spiranthes casei)

  • flowers: reddish
  • flowers: pubescent on back
  • flowers: nodding or horizontal
  • flowers: SINGLE rank
  • flowers: later blooming: August-September
  • flowers: off-white: yellowish-white
  • flowers: less than 8mm long
  • habitat: drier ground than Nodding Ladies' Tresses (Spiranthes cernua)

Southern Slender Ladies' Tresses (Spiranthes gracilis) and Northern Slender Ladies' Tresses (Spiranthes lacera)

  • flowers: lip somewhat ragged
  • flowers: smallest of all the Ladies' Tresses
  • flowers: lateral sepals spreading outward and down
  • flowers: greenish lip
  • leaves: Northern Slender Ladies' Tresses: present at flowering time
  • leaves: Southern Slender Ladies' Tresses: absent at flowering time
  • leaves: small ovate basal leaves
  • plant: inconspicuous
  • plant: easily mistaken at first glance for a grass