Native Orchids of Mount Robson Provincial Park

Mount Robson Provincial Park is one of our favorite places for hiking and backpacking and is conveniently located on the way to Edmonton, the home of one of our daughters.  Two summers, 2009 and 2010, we backpacked in the park for five days and the last two summers, 2011 and 2012, we've hiked there.  We've found it to have more native orchids than any other place we've hiked.

This post shows the different species and varieties we've found in the park, a total of nineteen, but we are fairly sure that there are five or six more that we have not seen.  Most of these we've seen flowering around the end of June and beginning of July at different elevations, but several do not bloom until later in the summer and we've had to make a point of hiking there in August to catch them.

The species and varieties we've found are:

Amerorchis rotundifolia, the Small Round-leaf Orchis

Calypso bulbosa var. americana, the Eastern Fairy Slipper

Corallorhiza maculata var. maculata, the Spotted Coralroot

Corallorhiza trifida, the Early Coralroot

Cypripedium parviflorum var. pubescens, the Large Yellow Lady's Slipper

Cypripedium passerinum, the Sparrow's-egg Lady's Slipper

Goodyera oblongifolia, the Giant Rattlesnake Orchis

Goodyera repens, the Lesser Rattlesnake Orchis

Listera borealis, the Northern Twayblade

Listera cordata var. cordata, the Heart-leaved Twayblade

Listera cordata var. cordata fma. viridens,
the green form of the Heart-leaved Twayblade

Piperia unalascensis, the Alaskan Piperia

Platanthera aquilonis, the Northern Green Bog Orchis

Platanthera dilatata var. dilatata, the Tall White Northern Bog Orchis

Platanthera dilatata var. albiflora, The Bog Candle

Platanthera huronensis, the Green Bog Orchis

Platanthera obtusata ssp. obtusata, The Blunt-leafed Rein Orchis

Platanthera orbiculata, the Pad-leaved Orchis

Platanthera stricta, the Slender Bog Orchis

There are two others we've seen in nearby areas, Cypripedium montanum and Coeloglossum viride var. virescens, the former to west of the park and the later to the east in Jasper National Park.  These almost certainly bloom within Robson as well.  We intend to look for them the next time we are in the area and have time to do some hiking, since we now know something of their habitats.

Cypripedium montanum, the Mountain Lady's Slipper

Coeloglossum viride var. virescens, the Long-bracted Green Orchis

There are probably a number of others within the confines of the park, though we have not seen them or seen any record of them.  They are fairly common species and are found in surrounding areas.  These are plants we would like to find within the park as well, though with several exceptions, we have seen them elsewhere and they are relatively common.

Corallorhiza mertensiana, the Western Coralroot

Corallorhiza striata var. striata, the Striped Coralroot

Listera convallarioides, the Broad-lipped Twayblade

Malaxis brachypoda, the White Adder's Mouth

Malaxis paludosa, the Bog Adder's Mouth

Spiranthes romanzoffiana, the Hooded Ladies' Tresses

Nineteenth and Twentieth Weeks, the Last Weeks of the Native Orchid Season - Bog Orchids and Ladies'-tresses

August 11-24

There will still be a few things blooming in the weeks to come at higher elevations, some Piperias, especially Piperia elongata, as well as some Spiranthes romanzoffiana, but these weeks are going to be the last that I mark with a post.  The two orchids featured were found at Mount Rainier National Park.  We spent several days there and found only these still blooming and these at the highest elevations.

The showiest of the two is Spiranthes romanzoffiana, the Hooded Ladies'-tresses.  We found them at several locations along the Longmire to Paradise Road and exactly where we would have expected to find them, in damp open meadows.  Interestingly, the Spiranthes we found near Paradise at 5400 feet elevation (1645 meters) were very tiny plants, only a couple of inches tall, blooming with Bog Gentians.

We found the other orchid, the Slender Bog Orchis, Platanthera stricta, in the wettest ditches along the way.  This very common orchid is not very showy, perhaps the least so of all our native orchids and probably goes unnoticed by most.  These were still in relatively good shape at the higher elevations where we found them and we said goodbye to the native orchid season with them and with a few photographs.

Eighteenth Week of the Native Orchid Season - Epipactis, Platanthera and Spiranthes

August 4-10

Two excursions and lots of orchids this week.  I went for an afternoon and visited some sites in Larrabee State Park south of Bellingham and found a lot of Epipactis helleborine, the Broad-leaved Helleborine.  As I've noted before, this is not a native but has colonized the coastal areas of the park and seems to be everywhere.  Due to its location along the railroad tracks, I believe that is how it probably came in, but it has spread along many of the trails and I suspect that foot traffic is the way it's spread.  Some call it a weed, but it is a rather attractive weed nonetheless.

I found not only the normally colored form varying from green and purple to green and pink, but also found the green-flowered form, Epipactis hellebronie fma. viridens.  The species has several other color forms as well with yellow or white flowers.  Many of the plants I found, however, had unusually small flowers, some less than 2cm (approximately a half inch) and very tightly packed on the stems.  I suspect this is due to a very dry summer which also probably limited the number of plants, since I did not find as many as I expected, even though I visited a number of sites.

Later in the week we made a trip to eastern Washington and left time to explore the mountain pass in North Cascades National Park where we found four orchids still blooming, though it is obvious that the season is winding down and winding down early, due to a very dry summer.  Around Diablo Lake and the dams we found Spiranthes romanzoffiana, the Hooded Ladies'-tresses, but they were nearly finished there.  Further up in the mountains, however, they were in full bloom and we found hundreds of them in damp and sunny areas, especially to the west of Washington pass.

In those same areas we found two Platantheras still blooming, Platanthera dilatata var. dilatata, the Tall White Northern Bog Orchis, was still blooming.  It is distinguished from the other varieties of this species by a spur that is approximately the same length as the lip.  With it was blooming the ubiquitous Platanthera stricta, the Slender Bog Orchis, found in every wet ditch in the Cascades at this time of the year.  Both of these species were finished at lower elevations and even at these highest elevations showed signs of the fact that they would soon be finished.

We also found one plant of what appeared to be a natural hybrid of Platanthera stricta and one of the varieties of Platanthera dilatata, with the color and lip of the former species and the spur of the latter.  What the name of this hybrid would be I am not sure, but the hybrid of another variety of Platanthera dilatata and Platanthera stricta is known as Platanthera xestesii, Estes Hybrid Rein Orchis.  The green Platantheras are infinitely variable, however, and intergrade with one another and so I am not at all sure what exactly we saw or even whether this is indeed a natural hybrid.

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