The most common Dryas in Alberta, and very widespread, from the foothills (I think it follows some river valleys even farther down out of the actual hills) to alpine areas (Lori can better comment on its presence in real alpine places, though I know it's common in places such as at the foot of the Athabasca Glacier, a site with colonising and alpine flora, though technically it's below the treeline).
These first photos are from May 31, 2011, near Nordegg, Alberta in the foothills. This area is naturally forested, but low growing plants take full advantage of cleared areas near the highway...
1 Dryas drummondii with the other ubiquitous sub-shrub- Arctostaphylos uva-ursi
2-4 typical nodding flower, they remain half open like this
5 brighter foliage comes with new growth, this is overwintered foliage
6 the mats cover large areas, with many other plants growing through them
7 an atypical upturned flower
8,9 the mats extend across the open areas and into the edge of the woods, which will likely shade out the Dryas over time, depending how far back the road maintenance keeps the trees
10 a view from the edge of the trees to the highway..
