The
photo at right shows bog saxifrage (var. montanensis)
as seen about 1 mile below the top of the South Loop Road at Steens Mt. in southeastern
Oregon. Note the thick stem with short side branches, and
the dry, withered stem from the previous year at its base.
Also known as Oregon saxifrage, bog saxifrage is a large, stout 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 4-13 cm long, oblanceolate or elliptic-oblanceolate or narrowly obovate, narrowing gradually to a winged petiole that ranges from 1-6 cm long. In variety montanensis, the margins are entire to coarsely toothed or wavy. The blades are nearly glabrous to lightly haired on both surfaces and often ciliate-margined at the base of the blade and along the petiole (See photo below.).
The inflorescence may be open and diffuse or elongate and narrowly cymose-paniculate. In variety montanensis , the 5-10 side branches are up to 8 cm apart and ascending, the lower branches much shorter than those of variety oregana. Many gland-tipped hairs may be found in the inflorescence. The pedicels are 0.5-3.5 mm long. The sepals typically are strongly reflexed or occasionally spreading, are widely triangular and measure 1.3-2.5 mm long. 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, and range from 1.5-4 mm long and 0.6-2.5 mm wide with rounded to somewhat pointed tips. The filaments are 1-2 mm long, topped by pale orange anthers from 0.5-0.7 mm long. The 2 styles are short and thick. The ovary is about one-half inferior at flowering, becoming more superior as the fruit ripens.
On the Steens Mt., variety montanensis hybridizes with S. nidifica, and both may appear somewhat similar there.
Currently, bog saxifrage is not split into 3 varieties. The old classification showing the difference between the varieties is shown below for interests sake.
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. 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. 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.