Saturday, December 13, 2014
Neottias of the Pacific Northwest
The species, known until recently as Listeras, have been moved into the genus Neottia. There are four such species in the Pacific Northwest and three additional North American species. The four species treated in this article are Neottia banksiana, borealis, convallarioides, and cordata. Until this past summer we had only seen three of the four species from our area, but finally found the last and rarest of them, Neottia convallarioides in the Mount Rainier area of Washington.
Neottia banksiana, the Northwestern Twayblade, is very common in our area and can be found along nearly every mountain trail in the Cascades, the Olympics and Canadian Rockies. It is a fairly tall plant (up to 30 cm) and its height is usually the first clue to its identity (the other tend to be smaller). The 1 cm flowers, up to 15 per stem, are not showy but with the darker markings on the lip are attractive especially when seen close up.
Neottia borealis, the Northern Twayblade, reaches only 20 cm in height and is usually smaller, lives up to its name. It becomes more common the further north one goes. It is found into Montana, Idaho and Washington but is very rare that far south. It has up to 15 flowers per spike and the flowers are a pale watery green that looks translucent in good light. Like the other species it size and the color of the flowers mean that it usually goes unnoticed.
Neottia convallarioides, the Broad-lipped Twayblade, is quite rare. It is known, for example, from only a few locations in the state of Washington. It seems to prefer wetter locations and where we have found it is growing near seeps and springs. It, too, has up to 15 clear green flowers and grows to 30 cm tall, though it is usually much less than that. Neottia banksiana is often mistaken for it, but when once seen is unmistakable in that it lacks any dark markings on the lip.
Neottia cordata, the Heart-leaved Twayblade, is another very common species. We have seen it growing by the thousand in open mossy areas in the Cascades. It is usually very small (15 cm or less) with as many as 25 tiny flowers that are less than 1 cm in size. It has two varieties, and two color forms, green and reddish. The varieties are var. cordata with narrower leaves and a shorter lip and var. nephrophylla with wider leaves and a longer lip.