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Alpine flora of the Canadian Rocky Mountains

Chapter 27: Parnassiaceæ Grass-of-Parnassus Family
By Stewardson Brown
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About This Book

A concise field manual that surveys the alpine and subalpine plants encountered along the Canadian Rockies and the Selkirks accessible by the trans-mountain railway, emphasizing distinct regional assemblages and plant adaptations to differences in moisture and exposure. Species are arranged by botanical families with general keys to families and genera; treatments include ferns, conifers, shrubs and the majority of herbaceous flowering plants while excluding grasses, sedges, and willows. Descriptions are accompanied by plates, watercolour illustrations and photographs, and the text relates local taxa to comparable mountain floras while noting characteristic species, habitats and elevational ranges.

Parnassiaceæ
Grass-of-Parnassus Family

Smooth bog-herbs with a rosette of basal leaves and generally one or a few alternate stem leaves and solitary, terminal flowers. Flowers perfect; calyx generally 5-lobed to near the base; petals 5; perfect stamens 5; staminodia (imperfect stamens) in clusters at the base of each petal; stigmas 4.

Parnassia fimbriata Banks. Fringed Grass-of-Parnassus.

Leaves tufted at the base on petioles 2—6 inches long; blades reniform or broadly cordate, ¾—½ an inch wide, thin, smooth, with about 7 principal veins. Flowers ¾ of an inch or more broad on a scape 8—12 inches high with a small cordate clasping bract about the middle; sepals ¼ of an inch long, elliptic, obtuse; petals obovate, pure white, fringed at the base, staminodia united into 5 fleshy obovate scales.

Common throughout the region in springy places and damp mossy banks at the lower altitudes, flowering during July.

Parnassia montanensis Rydb. & Fernald. (½ Nat.)
Marsh Grass of Parnassus.

Ribes lacustre (Pers.) Poir. (¼ Nat.)
Swamp Gooseberry.

Parnassia montanensis Rydb. and Fernald. Marsh Grass-of-Parnassus.

Leaves tufted at the base on short petioles, blades ovate with a cordate or rounded base ¾ of an inch long. Flowers solitary, on scapes 8 inches or more high with a large ovate bract below the middle; sepals lanceolate, acute, ¼ of an inch or more long, petals oval to elliptic only slightly larger than the sepals; staminodial scales with 7—9 gland-tipped filaments.

Throughout the Rockies in marshy ground and shaded river shores; flowering in June and early July.

Parnassia parviflora DC. Small-flowered Grass-of-Parnassus.

Scapes slender, 4—12 inches high, usually bearing a clasping oval leaf at the middle. Basal leaves on slender petioles, oval or ovate, narrowed at the base, not cordate, ½—1 inch long. Flowers about ⅓ of an inch broad, sepals equalling or somewhat shorter than the elliptic sessile petals; staminodia 5—7 at the base of each petal.

In wet gravelly places at the lower altitudes throughout the Rockies; flowering in July.

Parnassia Kotzebuei Cham. and Schl. Alpine Grass-of-Parnassus.

Much smaller than the preceding species. Basal leaves few on petioles less than an inch long; blades broadly ovate, ½ an inch long. Flowers on slender scapes 2—4 inches high, without any bract; sepals oblong, about ¼ of an inch long, equalling or exceeding the elliptic or oval 3-veined petals; staminodia short with 3—5 slender filaments.

Throughout the Rockies at high altitudes on the gravelly borders of alpine ponds or brooks, a very diminutive species, flowering in July.