Slender Bog Orchis (Platanthera stricta)

In the Pacific Northwest this is by far the most common species and the least attractive.  Its plain green flowers are only about a cm in size and though abundant, as many as 50 on a spike, would pass unnoticed in most cases, even though the plants are around 100 cm tall.

We have seen this species with stems as thick as a man's finger and as slender as a heavy wire.  It is identified by its narrow lip and inflated spur and ranges across the Pacific Northwest as far south as California and as far east as Montana.

Pad-leaved Orchis (Platanthera orbiculata)

Platanthera orbiculata is a very striking species, very different from the other plants in the genus.  It ranges in a great arc from Washington, Idaho and Montana, through Canada and Alaska and down into the Appalachian Mountains as far south as North Carolina and Georgia.

Like P. obtusata, it is usually found in woodlands rather than in wet and marshy areas. and is easily recognizable not only by its location, but also by its two large pad-like leaves and its flowers which are whitish-green and look like a dragonfly in flight.

The plants are 60-57 cm tall and the individual flowers, usually 10-15 of them, approximately 5 cm in size, among the largest flowers in the genus.  It also blooms a bit later than the other Platantheras.  We've found it only when the other species were nearly finished flowering in early August.

Blunt-leafed Rein Orchis (Platanthera obtusata subsp. obtusata)

This is one of the easier Platantheras to identify since its 1 cm flowers are whitish in color and of a different shape from P. dilatata, aquilonis, huronensis, stricta and such species.  It is also much smaller in plant size, rarely more than 30 cm tall.

It can also be identified by the fact that it has only one leaf near the base of the plant and by the fact that it is often found in woodlands rather than open marshy areas.  There is a smaller, fewer-flowered subspecies, but that is confined to northern Alaska and Eurasia.

The species is found across Canada and in the United States only in Alaska, Washington, Idaho, Montana, Colorado, Massachusetts, and the upper Great Lakes region.  It increases in numbers the farther north one traces it, being rare in the southern parts of its range.

Green Bog Orchis (Platanthera huronensis)

Always found in wet areas, as its name indicates, this is one of the less attractive species in the genus.  Its greenish flowers are a little larger than 1 cm and as many as 50-75 flowers may be closely crowded together on the stems.

This is one of the few species we have found growing at high altitudes, and because it is usually then growing in the open, the plants are quite short, about 10-15 cm, while otherwise they grow as tall as 100 cm.  It is also very abundant and can be found in large numbers.

This species, too, is found all across Alaska, Canada and the northern United States.  There are supposed to be some natural hybrids, but the green-flowered species themselves are so difficult to distinguish that we have made no effort to distinguish the hybrids.

 
This, I believe, is a very small form of Platanthera huronensis, only a few inches tall, growing in an open area at about 5000 ft in the Canadian Rockies near Berg Lake.

Estes Hybrid Rein Orchis (Platanthera x estesii)

This plant is a natural hybrid between Platanthera dilatata var. albiflora and Platanthera stricta.  We have found it in several places where these two species grow together.

It looks more like P. dilatata than P. stricta, like a greenish-white version of the former species.  The plant and flower size are nearly the same also as for that species.

Bog Candles (Platanthera dilatata)

This is the easiest of the Platantheras to identify on account of its pure white flowers and its sweet scent. Its white flowers make it more visible than some of the other species, and its scent perfumes the air wherever it grows.  It is very common, but always worth seeing.

We have found it on almost every hiking trip and along the roadsides in every mountainous area of the Pacific Northwest, often by the thousands. Along the Yellowhead Highway in the mountains of British Columbia, for example, we have seen it blooming mile after mile in every marshy spot.

There are three varieties of this species, distinguished by the length of the spur, which probably indicates different pollinators for each. Var. albiflora has a spur shorter than the lip, var. dilatata a spur the length of the lip and var. leucostachys, a spur much longer than the lip.

The plants can be quite short, around 20 cm, but are often much taller, around 100 cm. The 2 cm flowers are crowded along the length of the stems in large numbers, often over 100 flowers per plant. We have noticed that quite often the lip catches in the dorsal sepal so that the flower does not open completely.

There are several natural hybrids of this species and its varieties with P. stricta and sparsifolia.  These usually resemble P. dilatata, except for the flower color which is greenish, rather than pure white.  The only one of these natural hybrids that we've seen has been sufficiently different to warrant a separate post.

This species also ranges from Alaska across Canada and the northern United States as far south as Pennsylvania and Indiana, California and New Mexico. Varieties albiflora and leucostachys, however, are more limited in range, and can be found only in the western United States and Canada.

Variety albiflora

Variety dilatata

Variety leucostchys

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.