[Bog and Rein Orchids: The Genus Platanthera in the Cascade Mountains of Oregon and Washington]
Dilated Bog Orchid, Scentbottle, Scent Bottle Orchid, White Bog Orchid, White Rein-orchid, Tall White Bog Orchis
Platanthera dilatata var. dilatata
Synonyms: Habenaria dilatata, Habenaria dilatata var. angustifolia, Habenaria dilatata var. dilatata, Limnorchis dilatata
This photo shows a close-up of the flower of white bog orchid. This is variety dilatata which has a spur that is roughly equal to the length of the lower lip. The photo was taken along the Timberline Trail about one-half mile above Lambertson Butte in the Mt. Hood Wilderness........August 2, 2007.
Characteristics:
White bog orchid is a lovely orchid of moist places, with single, stout, hollow
stems to 25-50 cm high. The fleshy sheathing leaves cover the lower part of
the stem. The lower leaves range from 5-20 cm long, and become reduced in size
upwards on the stem.
The flowers are white, showy, and numerous, forming a spike at the apex of
the stem. The flowers are about 15-18 mm long with a lanceolate lip from 6-8
mm long, which is dilated at the base. The spur is about as long as the lip.
The upper sepal and 2 petals form a hood. The lower 2 sepals spread to each
side of the flower.
Two varieties of white bog orchid may be found in the Columbia River Gorge.
Both are similar, but variety dilatata has a thicker spur which is straighter
and about as long as the lip (See photo at right.). Variety leucostachys
has a slender, strongly curved spur which is about half as long as the lip.
Habitat:
White bog orchid is a plant of wet meadows, moist forest edges, and seeps.
Range:
Habenaria dilatata is found over much of North America. It may be found
from Alaska to Greenland and hence south to California, Nevada, New Mexico,
Utah, South Dakota, Michigan, Pennsylvania, and New York.
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These 2 photos show additional close-ups of the flowers of white bog orchid. This is variety dilatata which has a spur that is roughly equal to the length of the lower lip. The spur may be slightly shorter, slightly longer or equal for this variety. Variety albiflora has a spur which is significantly shorter than the lower lip. Variety leucostachys has a spur that tends to be significantly longer than the lower lip and it generally is very slender in cross-section. Note the thick spurs in these photos, typical of variety dilatata. Care must be given when identifying populations as all three varieties may be found within the same location. Both photos were taken along the Timberline Trail about one-half mile above Lambertson Butte in the Mt. Hood Wilderness........August 2, 2007.
The photo above shows a close-up of the flower of dilated bog orchid. Note the long, narrow lower lip which is longer than the thick spur. Note also the two upper petals and partially fused sepals which form a hood. Photographed in wetland forest near Willard Springs in Conboy Lake NWR.........June 15, 2008.
Wetland habitat of the white bog orchid as seen at Willard Springs, Conboy Lake National Wildlife Refuge.........June 20, 2013.
White bog orchid blooming in a wet portion of Bottle Prairie, Mount Hood National Forest........July 17, 2016.
Paul Slichter