[Saxifrages: The Genera Micranthes and Saxifraga East of the Cascade Mts. of Oregon and Washington]

Brook Saxifrage, Stream Saxifrage

Micranthes odontoloma

Synonyms: Saxifraga aestivalis, Saxifraga arguta, Saxifraga odontoloma, Saxifraga puncata var. arguta

Close-up of a flower of Brook Saxifrage, Stream Saxifrage: Micranthes odontoloma (Synonyms: Saxifraga aestivalis, Saxifraga arguta, Saxifraga odontoloma, Saxifraga puncata var. arguta)

The photo above shows a close-up of the flower of brook saxifrage. Note the broad, rounded petals with 2 yellow dots at their base and the 10 club-shaped stamen filaments. Photographed along the Umatilla Rim Trail #3080, Umatilla N.F.........June 24, 2007.

Leaf of Brook Saxifrage, Stream Saxifrage: Micranthes odontoloma (Synonyms: Saxifraga aestivalis, Saxifraga arguta, Saxifraga odontoloma, Saxifraga puncata var. arguta)The photo at right shows a close-up of the leaf blade of brook saxifrage as photographed at Wildhorse Lake on the Steens Mt. of southeastern Oregon.........July 16, 2000.
Characteristics:

Brook saxifrage has recently been reclassified as Saxifraga odontoloma from S. arguta..

Also known as mountain meadow saxifrage, brook saxifrage is a perennial with a single, erect and leafless stem from 20-60 cm high arising from a cluster of basal leaves atop well-developed horizontal rootstocks. Bulblets are generally absent from the rootstocks at the base of the petioles. The herbage is glabrous below and somewhat glandular-hairy above, the hairs being tipped with red, purple or yellowish glands. The leaf blades are kidney-shaped with many (15-29) rounded to pointed teeth around the margins (See photo at right.). The margins are not double-toothed (as in Merten's saxifrage) and the teeth are about equal in size and evenly spaced. The blades are 2-8 cm wide and about 2/3 as long.

The inflorescence is found atop the bare stem. It consists of open, cymose panicles with the glandular-haired branches spreading and rising. The calyx is cleft almost its entire length of 1.5-2 mm. The 5 purplish calyx lobes are oblong-ovate or oblong-lanceolate. The 5 white petals are each orbicular in shape and spreading, from 3-4 mm long. The petals may all be equal in size, or 2-3 may be larger than the other 2. The base of each petals is rounded and clawed and bears to yellow dots (See photo above.). The 5 white stamens are about equal in length to the petals. The white filaments are narrowly club-shaped. The ovary is superior with 2 (up to 4) carpels which are fused 1/3-3/5 of their length. The ovary is red to purple in color.


Similar Species:

Merten's Saxifrage Saxifraga mertensiana: The leaf petioles and stems are covered with long, soft and spreading hairs. The leaf blades are similar in shape to those of brook saxifrage, but have double-toothed margins that are more deeply incised (up to 1/4 the distance into the center of the blade). The white petals are all equal in size. They are narrowly ovate, tapering gradually to a pointed tip and have abruptly tapered, clawed bases that lack 2 yellow spots. Often found on wet, shaded cliffs.


Habitat:

Brook saxifrage may be found in wet meadows and along streams or springs at higher elevations.


Range:

Brook saxifrage may be found from southern Alaska south through British Columbia to the Cascade and Olympic Mts. of Washington and Oregon and the Sierra Nevada of California to southern California It may be found east to Alberta and south through the mountains of Idaho, Montana, northeastern Oregon and in the Rocky Mts. south to Arizona and Mew Mexico.


Flower of Brook Saxifrage, Stream Saxifrage: Micranthes odontoloma (Synonyms: Saxifraga aestivalis, Saxifraga arguta, Saxifraga odontoloma, Saxifraga puncata var. arguta) - Inflorescence of Brook Saxifrage, Stream Saxifrage: Micranthes odontoloma (Synonyms: Saxifraga aestivalis, Saxifraga arguta, Saxifraga odontoloma, Saxifraga puncata var. arguta) - Sideview of the flower of Brook Saxifrage, Stream Saxifrage: Micranthes odontoloma (Synonyms: Saxifraga aestivalis, Saxifraga arguta, Saxifraga odontoloma, Saxifraga puncata var. arguta)

Close-up photos of the flowers and inflorescence of brook saxifrage as seen in a riparian along forest road #4030 on the northern slopes of Mt. Misery in the Umatilla N.F. of southeastern Oregon.........July 7, 2008. Note the petal-llike (petaloid) stamens and the asymmetrical petals.

Brook Saxifrage, Stream Saxifrage: Micranthes odontoloma (Synonyms: Saxifraga aestivalis, Saxifraga arguta, Saxifraga odontoloma, Saxifraga puncata var. arguta) - Brook Saxifrage, Stream Saxifrage: Micranthes odontoloma (Synonyms: Saxifraga aestivalis, Saxifraga arguta, Saxifraga odontoloma, Saxifraga puncata var. arguta)

Brook saxifrage as seen along the East Fork Lostine River about 2 miles upstream along Trail #1662 from Two Pan trailhead, Eagle Cap Wilderness.........August 4, 2016.

Leaf of Brook Saxifrage, Stream Saxifrage: Micranthes odontoloma (Synonyms: Saxifraga aestivalis, Saxifraga arguta, Saxifraga odontoloma, Saxifraga puncata var. arguta)

This photo shows a close-up of the leaf of brook saxifrage as seen in a riparian along forest road #4030 on the northern slopes of Mt. Misery in the Umatilla N.F. of southeastern Oregon..........July 7, 2008.

Leaves of Brook Saxifrage, Stream Saxifrage: Micranthes odontoloma (Synonyms: Saxifraga aestivalis, Saxifraga arguta, Saxifraga odontoloma, Saxifraga puncata var. arguta)

The leaves of brook saxifrage as seen in a riparian zone along the Canyon Mountain Trail #218 at upper Little Pine Creek, Strawberry Mountain Wilderness...........August 1, 2011.

Paul Slichter