Listera cordata var.nephrophylla or Western Heartleaf Twayblade can be found in shaded well drained humus rich forests. This species is known to be more robust with larger leaves and overall plant size compared to others in the genus Listeria. The small green to yellowish green flowers number up to 25. The flowers are never red. The lip splits into two narrow lobes. The leaves are heart shaped, paired and half way up the stem. The distribution is Washington, Oregon, California and the Rocky Mountains north to Alaska.

The common name Heartleaf Twayblade refers to the heartshaped leaves of opposite pairs. The botanical name Listera cordata was named after M. Lister, an English naturalist of the 17th and early 18th centuries. While cordata means heart shaped, the Heartleaf Twayblade is also known as Mannikin Twayblade.

The Heartleaf Twayblade is a perennial that arises from a rhizome. The plant is not tall and the flowers are not showy, but the leaves are intriguing. The flowers are green and purple with 2 small prongs at the base of a cleft lip, in wandlike clusters. The leaves are heart shaped, paired and half way up the stem. The Heartleaf Twayblades habitat is in coniferous mossy woods, subalpine forests, swamps and along wooded streams.

The Heartleaf Twayblade has a faint unpleasant odour that attracts flies and fungus gnats. Charles Darwin studied the intricate pollination mechanism of the Listera species. When an insect enters the split lip it touches a sensitive trigger at the tip of the column. A squirt of viscous fluid with two pollinia covers the insects back. The startled insect then flies away carrying the pollen away.

You can find Heartleaf Twayblade along the trail to Comet Falls on Mount Rainier. As a child, I could find Heartleaf Twayblades along Coulter Creek in Allyn, Washington.

• Height: 2 -10 inches
• Flower Size: 1/8 – ¼ inch
• Blooms: June to July
  
  Photos courtesy of: © Melissa Rathbun-Holstein, Coulter Creek, WA
  
  Photos courtesy of: © Tina Taylor, Tahuya State Forest, WA
  
  
  
  

Listera banksiana or Northwestern Twayblade Listera banksiana or synonym Listera caurina or Northwestern Twayblade is a native orchid to Washington state. The word caurina means the northwest wind. This perennial forms slender creeping rhizomes. The Listera banksiana can be found in moist to wet, mossy coniferous forests, wet meadows, stream banks from low to sub-alpine elevations. The leaves are very hairy, single pair, opposite, near mid-length of stem. The leaves are egg shaped and broad with a pointed tip. The 5 to 25 flowers are a pale green to yellowish. The lip is rounded and with a pair of horn-like teeth at the base. The distribution is from southern Alaska south to northwestern California. The Listera banksiana also occurs in Wyoming State. Height: 5 to 25 cm Flower Size: 10 mm Blooms: June to September Photos courtesy of: © Melissa Rathbun-Holstein, Coulter Creek, WA Listera convallarioides or Broad-leaved Twayblade Listera convallarioides or Broad-leaved Twayblade is a native orchid to Washington state. This perennial forms slender creeping rhizomes. The leaves are a single pair, opposite, mid-length of stem, broadly ovate. Listera convallarioides can be found growing in damp mossy coniferous forests and mix forests, bogs, swamps, wet thickets and peaty barrens. The Listera convallarioides has 20 yellow-greenish flowers. The sepals are narrowly lanceolate. The petals are similar to sepals but narrower. The lip is a broadly wedge-shaped with a shallow notch at tip. The distribution is British Columbia across Canada to Newfoundland, south to northern California, Utah, Colorado, Minnesota, Wisconsin, Maine, Nova Scotia and the Aleutian Islands. Height: 5 to 25 cm Flower Size: 15 to 20 mm Blooms: June to August Photos courtesy of: © Jim Riley Listera borealis or Northern Twayblade Listera borealis or Northern Twayblade is a native orchid to Washington state. This perennial herb forms slender rhizomes with fibrous roots. You can find Listera borealis in coniferous and hardwood forests. The two leaves are near middle of stem, roughly opposite. The leaves are egg-shaped to elliptic, abruptly tapered to the base, smooth. The flowers are somewhat open. The Listera borealis flowers are green or yellowish-green in color. The sepals are broadly lanceolate. The petals are similar to the sepals. The lip is broadly oblong and widely notched at tip. The distribution is Alaska thru Newfound and south to Washington. Other states include Idaho, Montana, Wyoming, Utah and Colorado. Height: 8 to 25 cm Flower Size: 10 to 25 mm Blooms: June to July Photos courtesy of: © R.V. Rasmussen Listeria Articles Native Orchid Conservation Inc., March, 2002 Native Orchid Conservation Inc., December, 2004