A day-trip to collect specimens for a couple research projects earlier this week yielded an opportunity to photograph these small western alpine laurels. Growing at an elevation of 1920m (6300 ft), these diminutive plants (10cm / 4in) are referable to the broadly distributed Kalmia microphylla var. microphylla of western and northern North America. A second variety is recognized by the Flora of North America, Kalmia microphylla var. occidentalis, which tends to be both taller (sometimes to 80cm) and distributed only from Alaska to Oregon at lower elevations. Anatomically, leaf blade shape and dimensions are also used to distinguish the two varieties, with variety microphylla having shorter, stouter leaves.
According to Flora of North America, flower colour is “rose-purple, rarely white”, so I was fortunate to find one of the white-flowered plants. Only one small section, perhaps 0.5m2, of the entire local population of these plants was white, so it is possible that the white-flowered individuals were growing clonally.