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Idaho Mountain Wildflowers

Saxifrage Family, Saxifragaceae

The word “saxifrage” is derived from the Latin frango meaning “I break” and saxum meaning “rock.” Pliny (23 AD-79 AD) in his Natural History, wrote that the name saxifragum (“stone-breaker”) referred to the plant’s supposed ability to dissolve kidney and bladder stones. More likely, however, it reflected the plants’ growth habit, for saxifrages often grow in rocky clefts, seemingly having broken the stone apart. The family is not a large one, consisting of about 30 genera and 325 species. The plants are mostly herbaceous (non-woody). Although the family is distributed throughout the world, most members are found in the north temperate zone, often in inhospitable surroundings (desert, arctic, alpine, bogs and as aquatic forms). The family has little economic importance, although a few are used in folk medicine and others find a place in ornamental gardens. Saxifrage flowers usually have five sepals, five petals, and ten stamens. As will be seen on the following pages, many plants in this family have clusters of small flowers borne atop a long stem with a basal rosette of toothed leaves, a useful identifying feature.

Mountain saxifrage, Saxifraga occidentalis S. Watson (left, right) blooms in early summer. preferring the moist ground of mountain meadows and the banks of mountain lakes. Its stem that gives off many stemlets each bearing a cluster of white flowers. Each flower has two prominent red carpals that mature into a two-parted capsule (“follicle”)

Diamond leaf saxifrage, Saxifraga rhomboidea Greene (left, right) is quite similar to the mountain saxifrage shown above, differing in the shape of its leaves (reflected in rhomboidea) and having light colored fruiting bodies. It is not uncommonly seen in the mountains of Central Idaho. Several other saxifrages, similar to this and to the mountain saxifrage, also occur in our mountains.

Wood, or woodland saxifrage, Saxifraga mertensiana Bong. (left, right) grows in shaded, moist situations commonly on or near streambanks. It is found at all elevations, as high as treeline.The plants are tall with long stems bearing small flowers. The round, scalloped leaves as well as its growth situation help with identification. It is native to the Pacific coastal states from Alaska to California and east to Alberta, Idaho and Wyoming.

Purple saxifrage, Saxifraga oppositifolia L. (left, right), The purple saxifrage forms dense cushions on the rocky ground of alpine tundra. The flowers, borne on almost non-existent stems, bloom while there is snow on nearby slopes. Its tiny, opposite leaves are tightly arrayed. Striking pink to purple, five-petaled flowers range up to an inch in diameter. This is a circumboreal arctic/alpine plant found not only in our mountains, but throughout the northern part of the northern hemisphere and in the alpine ranges of the Old World.

Brook saxifrage, Saxifraga odontoloma Piper (left), , formerly Saxifraga arguta, is typical of plants in the genus Saxifraga in having a basal cluster of leaves and a long stem bearing many small flowers. The brook saxifrage is common in our mountains, often turning streambanks green with its leaves. Identify the plants by their attractive, bright green, deeply scalloped, oval or fan-shaped leaves. These give the plant both its old and new species name (both mean “toothed”). The brook saxifrage is able to thrive in varying light intensities, growing equally well in bright sunlight or deep shade.

Poker alumroot, Heuchera cylindrica Douglas ex Hook. (right) is quite similar in appearance and in growth habit to the gooseberry-leaved alumroot shown below, differing mainly in the shape of its leaves. There is considerable difference in this plant’s morphology from place to place and even from plant to plant, and six different varieties are recognized that have minor variations in leaf shape. Unlike Heuchera grossularifolia, the petals are sometimes absent in the flowers of this species.

Gooseberry-leaved alumroot, Heuchera grossulariifolia Rydb. (left, right) blooms from late spring well into the summer, favoring cliffsides (where it usually grows as a solitary plant) and rocky ground where it may grow in clusters, from mid-elevations to alpine tundra. The species name is derived from the resemblance of its leaves to those of gooseberries. Its small flowers have five sepals joined to form a bell-shaped receptacle that almost hides the petals. The popular name, alumroot, is derived from its puckery taste, for the roots and stems contain a high concentration of tannin. The generic name honors Johann Heinrich von Heucher (1677-1747), Professor of Medicine at Wittenberg in Germany.

Five-stamen mitrewort, Mitella pentandra Hook. (left) and Side-flowered mitrewort, Mitella stauropetala Piper (right) are two of the four species of Mitella that grow in Idaho. Mitellas prefer moist environments and are usually found in shaded woods and along stream banks. As with many other plants in the saxifrage family, the plants’ basal leaves are disproportionately large when compared to the tiny flowers (greatly magnified in these illustrations) that occupy the end of long stems. The bizarre little flowers with five skeletal petals will be easily recognized when first seen. The word mitella is a diminutive form of the Latin mitra (“hat” or “cap”), a reflection of the shape of the plants’ fruiting body ,said to resemble a bishop’s hat. The name pentandra mirrors the common name "five-stamen,"and stauropetala, from the Greek ,means "cross-petal" for the shape of its attenuated petals.

Smallflower woodlandstar, Lithophragma parviflorum (Hook.) Nutt. ex Torr. & A. Gray (left). The woodlandstars (also “prairiestars”) are eye-catchers, thanks to their cleft white petals. Prominent calyces with five pointed tips cup the flowers. The petals have, depending on the species, three, five, or seven lobes. Small flower clusters are borne atop long, reddish to purple colored stems that arise from a basal cluster of lobed leaves. Woodland stars are spring-blooming montane plants, scattered through the sagebrush, in mountain meadows, and along stream banks, where they bloom into the summer at higher elevations.

Bulbous woodlandstar, Lithophragma glabrum Nutt. (right) was until recently classified as Lithophragma bulbifera Rydberg. The plant often forms tiny bulbs at the base of the flowers and leaves and these sometimes replace these structures. Its white-to-pinkish petals are rather attenuated and usually have five deeply dissected lobes, unlike the woodlandstar shown on the left.  The bulbous woodlandstar blooms quite early in the spring . The name, Lithophragma is derived from the Greek lithos for “stone” and phragma meaning “wall,” from the plants’ tendency to grow in rocky places. While bulbils are common in this species, other woodlandstars may also produce them.

Threeleaf foamflower, Tiarella trifoliata L. var. unifoliata (Hook.) Kurtz (left; right) also known as the coolwort, and the laceflower) prefers deep woods and well-shaded stream banks. Tiny, white, five-petaled flowers are borne in small clusters (“panicles”) on stemlets arising from a single long stem. The varietal name, unifoliata, differentiates this variety from var. trifoliata (shown on the right) in which the leaves are divided into three separate leaflets, rather than the single, lobed leaves of the plant shown here.

Grass-of-Parnassus family, Parnassiaceae

Fringed grass-of-Parnassus, Parnassia fimbriata K. D. Koenig (right, left). Parnassia species were, until recently, members of the saxifrage family. Parnassia palustris L. (not shown), a circumboreal, subalpine and alpine plant that grows throughout the northern hemisphere (including northern Idaho, is the original grass-of-Parnasssus. The name was given by Dioscorides who associated the plant with the Parnassus Range in Greece, where it grows today. Our plant,  Parnassia fimbriata ,is almost identical except for its fringed (“fimbriated”) petals. It blooms from midsummer on in swampy mountain meadows, and along the banks of slow moving streams, at montane to alpine elevations. The plants have single white flowers atop naked stems that emerge from basal clumps of kidney-shaped leaves. Five stamens emerging from between the petals are tipped with club-like yellow anthers. A yellow “staminode”—a modified, sterile, yellow nectar-secreting stamen—is located at the base of each petal.

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