Bog saxifrage from the upper slopes of Saddle Mountain in the Coast Range of northwestern Oregon........May 21, 2009. This is the former Micranthes hitchcockiana.
Bog saxifrage is a large, strong perennial with an erect, usually simple although occasionally several-branched stem from 30-120 cm tall. The herbage is smooth to having many long, soft, straight hairs near the base and becoming glandular-hairy near the inflorescence. The glands are yellow, pink, or purple. The leaves are 10-20 cm long, oblanceolate or elliptic-oblanceolate or narrowly obovate, narrowing gradually to a winged petiole. Depending on the variety, the margins may be entire, wavy, or coarsely toothed and smooth-surfaced to sparsely stiff-hairy.
The inflorescence may be open and diffuse or elongate and narrowly cymose-paniculate. Many gland-tipped hairs may be found in the inflorescence. The flowers are white or greenish-white, with 5 petals, often unequal in size, and occasionally with one or more missing. Individual petals are narrowly obovate to narrowly or widely oblong. The range from 2-4 mm long and 1-2.5 mm wide with rounded to somewhat pointed tips.
Var. oregana: Petals white, usually 3-5 mm long and about half as wide. The inflorescence is broadly pyramidal during early bloom, later more open with widely spreading branches. The ovary is usually not more than 1/3 inferior during bloom. Found west of the Cascade Mts. in Washington and Oregon and transitional to var. montanensis east of the Cascades. It may occasionally be found as far east as western Montana.
Var. montanensis: Petals white to greenish-white, mostly 2-3 mm long and usually less than half as wide. Inflorescence is narrow and elongated, with the branches of the panicle nearly erect. Ovary nearly 1/3-1/2 inferior during flowering. The calyx lobes, fruit, and filaments are usually green. Found in eastern Oregon, Idaho, Montana, Wyoming and Colorado.
Var. subapetala: Petals white to greenish-white, either absent or no more than 1 mm long and usually less than half as wide. Inflorescence is narrow and elongated, with the branches of the panicle nearly erect. Ovary nearly 1/3-1/2 inferior during flowering. The calyx lobes, fruits, and filaments may often be purple-tinged or reddish-purple in color. Found in central Montana and Wyoming.
Bog saxifrage may be found in wet meadows, bogs, and along streams.
Bog saxifrage may be found west of the Cascades from Snohomish County, WA south through the Willamette Valley of Oregon to the Sierra Nevada of California, and east through the Columbia River Gorge to eastern Oregon, and further east in montane Idaho, Montana, Wyoming and Colorado.