Nineteenth Orchid of the Season

The green-flowered Platantheras are not always easy to identify, but these are classic examples of the Northern Green Bog Orchis, Platanthera aquilonis.  The species is identifiable especially by its short, triangular lip, yellowish in color, and its tubular spur, shorter than the lip and curved forward.  These were photographed along the Richardson Highway to Valdez, Alaska, where they were growing with Platanthera huronensis, the Green Bog Orchis and Cypripedium passerinum, the Sparrow's-egg Lady's Slipper.  The two Platanteras were easily distinguishable even from a distance in that this species was much shorter than the other, only 6-8 inches tall (7-8 cm) and a darker green, while the other was around 18-24 inches (24-30 cm) tall and whitish-green.

Platanthera aquilonis

Platanthera aquilonis, the Northern Green Bog Orchis, is another of the hard-to-identify green Platantheras.  Indeed, because the Platantheras seem to interbreed quite freely it is sometimes impossible to identify them with certainly.  The distinguishing characteristics of this species are a yellowish lip, a spur that is shorter than the lip and curved well forward, and anther sacs that are low in the flower and form a kind of triangular shape.  The plant can be quite small to 60 cm tall and has numerous flowers, as many as fifty, more or less crowded on the flower spike.  The leaves are near the ground and up to 20 cm.  We do not see this species as frequently as some of the other green Platantheras and seldom in Washington, but have found it in a number of different locations in the Canadian Rockies in British Columbia and Alberta.

July 8

(Canadian Rockies)

July 10

(Canadian Rockies)

Platanthera aquilonis in the Canadian Rockies

Another green-flowered Platanthera, not as common as Platanthera huronensis and slightly more attractive than that species is Platanthera aquilonis, the Northern Green Bog Orchis.  Flowers and plants are very similar, however, and I always have difficulty telling the green-flowered Platantheras apart, though this has also to do with the fact that there are intermediate forms and natural hybrids between the species.  In any case, these are the plants and flowers that I've identified as Platanthera aquilonis.

I've identified these as that species on the basis of the yellowish lip which is more or less lanceolate in shape (lance-head like), and on the basis of the shape of the spur which is pretty much cylindrical.  These characteristics can be seen in the photos which were taken along the Maligne Lake Road in Jasper National Park, Alberta.  These were found growing with Coeloglossum viride and with Wood Lilies (Lilium philadelphicum) in rather wet areas.

Northern Green Bog Orchis (Platanthera aquilonis)

This is one of the green-flowered Platantheras, which I find incredibly hard to distinguish, both because many of the species are similar, but also because they interbreed and are, therefore found in many intermediate forms.

Platanthera aquilonis is one of the easier species to distinguish both because its lip is yellowish in color and because of its club-shaped spur. It is also one of the larger-flowered and more attractive species.

The individual flowers are less than 1 cm, but the plant, usually around 45 cm, bears many flowers, up to 60 per spike, and puts on a fair show as a result.

All the Platantheras have been and by some still are classified as Habenarias, and this species was once known not only as a Habenaria, but as H. hyperborea, now considered to be confined to Greenland.

We have not found this species as often as we have the other Platantheras, but when we've found it, it has been locally abundant, and always growing, as is the case with many in the genus, in marshy areas.

The plant ranges all across Canada and Alaska and across the northern United States as well and down into California and New Mexico.