''Boechera'' (rockcress) is a genus of the family

Brassicaceae Brassicaceae () or (the older) Cruciferae () is a medium-sized and economically important family of flowering plants commonly known as the mustards, the crucifers, or the cabbage family. Most are herbaceous plants, while some are shrubs. The leav ...

. It was named after the

Danish Danish may refer to: * Something of, from, or related to the country of Denmark People * A national or citizen of Denmark, also called a "Dane," see Demographics of Denmark * Culture of Denmark * Danish people or Danes, people with a Danish ance ...

botanist Tyge W. Böcher (1909–1983), who was known for his research in alpine plants, including the mustards ''

Draba ''Draba'' is a large genus of flowering plants in the family Brassicaceae, commonly known as whitlow-grasses (though they are not related to the true grasses). Species There are over 400 species: *'' Draba abajoensis'' Windham & Al-Shehbaz *'' ...

'' and ''Boechera holboellii''. According to recent molecular-based studies, ''Boechera'' is closely related to the genus ''

Arabidopsis ''Arabidopsis'' (rockcress) is a genus in the family Brassicaceae. They are small flowering plants related to cabbage and mustard. This genus is of great interest since it contains thale cress (''Arabidopsis thaliana''), one of the model organis ...

'' which also includes the widely known model plant ''

Arabidopsis thaliana ''Arabidopsis thaliana'', the thale cress, mouse-ear cress or arabidopsis, is a small flowering plant native to Eurasia and Africa. ''A. thaliana'' is considered a weed; it is found along the shoulders of roads and in disturbed land. A winter a ...

''. Until recently, members of this genus were included in the genus ''

Arabis ''Arabis'' ,''Sunset Western Garden Book,'' 1995:606–607 or rockcress, is a genus of flowering plants, within the family Brassicaceae. Description The species are herbaceous, annual or perennial plants, growing to 10–80 cm tall, usua ...

'', but have been separated from that genus based on recent genetic and cytological data. Unlike the genus ''Arabis'' (x=8) ''Boechera'' has a base chromosome number of x=7. Many taxa are

triploid Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contains ...

. ''Boechera'' is a primarily North American genus, most diverse in the western United States, and its distribution range also includes Greenland and the Russian Far East. The genus is poorly known, and species within are difficult to separate morphologically though some clearly distinct species are known. Most members of the genus are perennial plants with pubescent leaves with stellate

trichomes Trichomes (); ) are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a plan ...

, narrow curving fruits, and small white to purple flowers in elongated racemes. Relationships within the genus are unclear, and some eastern North American species, including ''

Boechera laevigata ''Boechera laevigata'' is a species of flowering plant in the mustard family known by the common name smooth rockcress. It is native to many areas of the eastern United States and Canada, where it grows in calcareous rocky woods and bluffs. It i ...

'', may belong to a clade distinct from the rest of the genus. A very interesting feature of many species of the genus is

asexual reproduction Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the f ...

, a process known as

apomixis In botany, apomixis is asexual reproduction without fertilization. Its etymology is Greek for "away from" + "mixing". This definition notably does not mention meiosis. Thus "normal asexual reproduction" of plants, such as propagation from cuttin ...

. Microsatellite data has revealed that some of the apomictic lineages are hybrids between two or more sexual parents.

Ecology

Species in this genus are one of the main food sources for the caterpillars of the butterfly ''

Pieris oleracea ''Pieris oleracea'', or more commonly known as the mustard white, is a butterfly in the family Pieridae native to a large part of Canada and the northeastern United States. The nearly all-white butterfly is often found in wooded areas or open pl ...

.''

Taxonomy

;Selected species *''

Boechera breweri ''Boechera breweri'' is a species of flowering plant in the family Brassicaceae known by the common name Brewer's rockcress. Distribution The plant is native to northern California and southern Oregon. It grows in rocky areas in mountains and ...

'' (Brewer's rockcress) *''

Boechera canadensis ''Boechera'' (rockcress) is a genus of the family Brassicaceae. It was named after the Danish botanist Tyge W. Böcher (1909–1983), who was known for his research in alpine plants, including the mustards ''Draba'' and ''Boechera holboellii''. ...

'' (sicklepod) *''

Boechera cobrensis ''Boechera cobrensis'' (syn. ''Arabis cobrensis'') is a species of flowering plant in the mustard family known by the common names Masonic rockcress and sagebrush rockcress. It is native to the western United States from eastern California to W ...

'' (sagebrush rockcress) *''

Boechera constancei ''Boechera constancei'' is a species of flowering plant in the mustard family known by the common name Constance's rockcress. It is endemic to California, where it is known only from the northern Sierra Nevada of Plumas and Sierra Counties. It ...

'' (Constance's rockcress) *''

Boechera crandallii ''Boechera crandallii'', or Crandall's rockcress, is found in Wyoming and Colorado where it is found on limestone chip-rock and stony areas, often among sagebrush. Flowering time is from May to June. According to chromosome counts by Rollins (19 ...

'' (Crandall's rockcress) *''

Boechera dentata ''Boechera dentata'', commonly called Short's rockcress, is a species of flowering plant in the mustard family (Brassicaceae). It is native to the eastern North America, where it is found in Canada and the United States. In the United States, it ...

'' (toothed rockcress) *''

Boechera depauperata ''Boechera'' (rockcress) is a genus of the family Brassicaceae. It was named after the Danish botanist Tyge W. Böcher (1909–1983), who was known for his research in alpine plants, including the mustards ''Draba'' and ''Boechera holboellii''. ...

'' (soldier rockcress) *'' Boechera dispar'' (pinyon rockcress) *'' Boechera falcatoria'' (Grouse Creek rockcress) *'' Boechera fecunda'' (sapphire rockcress) *'' Boechera gracilenta'' (Selby's rockcress) *'' Boechera gunnisoniana'' (Gunnison's rockcress) *'' Boechera hoffmannii'' (Hoffmann's rockcress) *'' Boechera holboellii'' (Holboell's rockcress) *''

'' (smooth rockcress) *'' Boechera lignifera'' (desert rockcress) *'' Boechera missouriensis'' (Missouri rockcress) *'' Boechera ophira'' (Ophir rockcress) *'' Boechera oxylobula'' (Glenwood Springs rockcress) *'' Boechera pallidifolia'' (Gunnison County rockcress) *'' Boechera patens'' (Spreading rockcress) *'' Boechera perennans'' (perennial rockcress) *'' Boechera perstellata'' (Braun's rockcress) *'' Boechera platysperma'' (pioneer rockcress) *'' Boechera pulchra'' (beautiful rockcress) *'' Boechera sparsiflora'' (sicklepod rockcress) *''

Boechera stricta ''Boechera stricta'' (syn. ''Arabis drummondii'', ''Boechera drummondii'', ''Turritis stricta''Al-Shehbaz, I.A., 2003. ''Transfer of most North American species of ''Arabis'' to ''Boechera'' (Brassicaceae)''. Novon 13(4): 381-391.) is a species o ...

'' (Drummond's rockcress) *'' Boechera tularensis'' (Tulare rockcress) *'' Boechera yorkii'' (Last Chance rockcress)

References

Brassicaceae genera {{Brassicales-stub