White Heather - Cassiope mertensiana ssp. mertensiana
Widespread and abundant in subalpine meadows and on well-watered stony slopes, between 5000 and 8000 feet. Photographed (in the rain) near Sluiskin Falls on August 2, 2013, at Shadow Lake on July 20, 2017, and at Reflection Lakes on July 12, 2014.