Lewisia

Ordinary Bitter root ( Lewisia cotyledon )

The bitter root ( Lewisia ) are a genus of the family of Montiaceae. It was in honor of Meriwether Lewis, an explorer of the American West, named.

Description

There are perennial, deciduous or evergreen herbaceous plants. They form a succulent caudex with a long taproot or, rarely, tuberous root. The leaves are spirally distributed in a rosette, either basal or on a stem. They are fleshy, entire, toothed or curled, gradually narrowing wedge-shaped at the base and tapering to a sessile or short broad petiole which encloses the stem more or less.

The inflorescences are formed axially racemes or Rispige grapes, rarely single flowers. Your stems rarely carry change permanent, alternate or arranged in whorls leaves, however, are mostly leafless. Are available at each flowering node two (up to nine ) slightly unequal bracts. The sepals are in pairs and are small or second- to ninth- and are then large and kronblattartig. 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 strongly with each other and / or with the fused petals. The spherical to ovoid ovary wearing 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 of the genus containing 17 species is restricted to the mountainous western North America, ranging from Alaska and Canada to 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 find very rare and only very locally. The main distribution point for the rare species is the state of California.

Sections

The genus is divided into the following sections. Section Lewisia: Plants with deciduous leaves, segmented pedicles, two to nine dry in fruit ripening sepals and petals falling as a whole. Brachycalyx B.Mathew: plants whose inflorescence consists falling leaves, only a single seat blooms, whose bracts and sepals touching. Section Erocallis B.Mathew: Plants with falling leaves and spherical tuber and well developed, standing in groups of three whorls leaves on the inflorescence stems. Section oppositifolia B.Mathew: Plants with deciduous leaves, long and slender flower stems and well-developed, constantly standing against leaves on the inflorescence stems. Section Pygmeae B.Mathew: Plants with sloping, mostly very narrow leaves and small branched inflorescences. Section cotyledon JEHohn ex B.Mathew: Plant with perennial evergreen and usually broad leaves and tall, rich branched inflorescences.

Species

• Lewisia brachycalyx Engelm. ex A. Gray: USA (California, Arizona, Utah), Mexico ( Baja California )
• Lewisia cantelovii JTHowell: USA (California, Nevada) Lewisia cantelovii var cantelovii: USA (California, Nevada)
• Lewisia serrata var cantelovii ( Heckard & Stebbins ) Hogan & Hershk. U.S. (California )

• Lewisia columbiana var columbiana: Canada ( British Columbia ), United States (Washington, Oregon)
• Lewisia columbiana var rupicola (English) CLHitchc. Canada ( British Columbia ), United States (Washington, Oregon)
• Lewisia columbiana var wallowensis CLHitchc. U.S. (Idaho, Montana, Oregon)

• Lewisia cotyledon var cotyledon: United States (Oregon, California )
• Lewisia cotyledon var heckneri ( CVMorton ) Munz: USA (California )
• Lewisia cotyledon var howellii ( S.Watson ) Jeps. U.S. (Oregon, California )

• Lewisia kelloggii var hutchinsonii Dempster: USA (California )
• Lewisia kelloggii var kelloggii: USA (California, Idaho)

• Lewisia rediviva var minor ( Rydb. ) Munz: USA (California, Nevada, Utah)
• Lewisia rediviva var rediviva: Canada ( British Columbia ), United States (Washington, Oregon, Idaho, Wyoming, Nevada, Utah, Colorado, California, Arizona)