Bitterroot

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Bitterroot
Common bitterwort (Lewisia cotyledon)

Common bitterwort ( Lewisia cotyledon )

Systematics
Class : Bedecktsamer (Magnoliopsida)
Eudicotyledons
Nuclear eudicotyledons
Order : Clove-like (Caryophyllales)
Family : Spring herb family (Montiaceae)
Genre : Bitterroot
Scientific name
Lewisia
Pursh
Lewisia rediviva , drawing by Mary E. Eaton
Lewisia columbiana

The Bitterwurz ( Lewisia ) are a plant kind from the family of Montiaceae . It was named in honor of Meriwether Lewis , an explorer of the American West.

description

They are perennial, deciduous or evergreen herbaceous plants . They form a succulent caudex with a long tap root or, rarely, a bulbous root. The leaves are spirally distributed in a rosette , either basal or on a stem . They are fleshy, entire, toothed or curled, gradually narrowing in a wedge shape at the base and sessile or tapering into a short, wide petiole that more or less surrounds the stem.

The axially formed inflorescences are panicles or paniculate racemes , rarely single flowers . Their stems rarely have alternate, opposite or whorled leaves, but are usually leafless. At each blooming node there are two (to nine) somewhat unequal bracts . The sepals stand in pairs and are small or in pairs to ninth and are then large and petal-like. The four to 19 petals are thin, often of different sizes and white, yellow, pink or magenta, often with darker nerves or stripes. The 4 to 50 stamens are free or are more or less fused with each other and / or with the petals. The spherical to ovoid ovary wears a long pen with three to eight scars rays . The capsule fruit contains few or many, brown or black seeds .

Systematics and distribution

The distribution area of ​​the genus containing 17 species is limited to the mountainous west of North America and extends from Alaska and Canada via the USA ( Rocky Mountains , Cascade Range , Sierra Nevada ) to Mexico ( Baja California ). The plants usually grow in small, scattered populations in ravines , on alpine plateaus , on rocks or gravel surfaces . Some species are common and widespread, but others are very rare and found only very locally. The main distribution center, also for the rare species, is the state of California .

Sections

The genre is divided into the following sections.
[1] Section Lewisia : Plants with falling leaves, segmented flower stalks, two to nine sepals that are dry when they are ripe, and flowers that fall as a whole.
[2] Brachycalyx B.Mathew : Plants with sloping leaves, the inflorescence of which consists only of a single sessile flower, the bracts and sepals of which touch.
[3] Section Erocallis B.Mathew : Plants with sloping leaves and a spherical tuber and well-developed leaves on the inflorescence stalk in three-whorls.
[4] Section Oppositifolia B.Mathew : Plants with sloping leaves, long and slender flower stalks and well-developed, opposite leaves on the inflorescence stem.
[5] Section Pygmeae B.Mathew : Plants with sloping, mostly very narrow leaves and slightly branched inflorescences.
[6] Section Cotyledon J.E.Hohn ex B.Mathew : Plants with perennial, evergreen and mostly wide leaves and high, richly branched inflorescences.

species

literature

  • Janet Elizabeth Hohn: Biosystematic studies of the genus Lewisia section Cotyledon (Portulacaceae). Dissertation. University of Washington, 1975, OCLC 19746060 .
  • Roy Elliott: The genus Lewisia . Alpine Garden Society, Woking, Surrey 1978.
  • Lauramay Tinsley Dempster: Portulacaceae: Lewisia . In: James Craig Hickman (Ed.): The Jepson Manual. The higher plants of California . University of California Press, Berkeley / Los Angeles 1993, ISBN 0-520-08255-9 .

swell

  1. ^ Brian Frederick Mathew: The genus Lewisia . Royal Botanical Garden Kew, Richmond (GB) 1989, ISBN 0-7470-2217-8 .
  2. ^ Special print from: Alpine Garden Society's Bulletin. Vol. 34 (1966) OCLC 787101856 .

Web links

Commons : Lewisia  - collection of images, videos and audio files