Mahonia

For the Oregon Governor's mansion, see Mahonia Hall.

Mahonia
Mahonia aquifolium fruit
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Order: Ranunculales
Family: Berberidaceae
Genus: Mahonia
Nutt.
Type species
Mahonia aquifolium
Species

See List of Berberis and Mahonia species

Mahonia is a formerly accepted genus of approximately 70 species of shrubs or, rarely, small trees with evergreen leaves in the family Berberidaceae, native to eastern Asia, the Himalaya, North America, and Central America.[1] They are closely related to the genus Berberis and as of 2023 the majority of botanical sources list it as a synonym for Berberis.[2][3][4][5]

However, there is still disagreement among botanists, and as recently as 2017 papers have been published arguing for the validity of the genus.[6] In addition, sources that are updated less frequently like the USDA Natural Resources Conservation Service PLANTS database have many plants listed in Mahonia.[7]

Most botanists prefer to classify Mahonia as a part of Berberis[8][9][10][11] because several species in both genera are able to hybridize, and because there are no consistent morphological differences between the two groups other than the leaf pinnation (Berberis sensu stricto appear to have simple leaves, but these are in reality compound with a single leaflet and are termed "unifoliolate"; additionally their branched spines are modified compound leaves[12]). However, recent DNA-based phylogenetic studies retain the two separate genera, by clarifying that unifoliolate-leaved Berberis s.s. is derived from within a paraphyletic group of shrubs bearing imparipinnate evergreen leaves, which are then divided into three genera: Mahonia, Alloberberis (formerly Mahonia section Horridae), and Moranothamnus (formerly Berberis claireae); a broadly-circumscribed Berberis (that is, including Mahonia, Alloberberis, and Moranothamnus) would also be monophyletic.[13]

Mahonia species bear pinnate leaves 10–50 cm (3.9–19.7 in) long with 3 to 15 leaflets, and flowers in racemes which are 5–20 cm (2.0–7.9 in) long. Several species are popular garden shrubs, grown for their ornamental, often spiny, evergreen foliage, yellow (or rarely red) flowers in autumn, winter and early spring, and blue-black berries. The flowers are borne in terminal clusters or spreading racemes, and may be among the earliest flowers to appear in the growing season.[14] The ripened fruits are acidic with a very sharp flavor.[15] The plants contain berberine, a compound found in many Berberis and Mahonia species which causes vomiting, lowered blood pressure, reduced heart rate, lethargy, and other ill effects when consumed.[15]

The genus name, Mahonia, derives from Bernard McMahon, one of the stewards of the plant collections from the Lewis and Clark Expedition. The type species of the genus is M. aquifolium.[6]

  1. ^ Flora of China Vol. 19 Page 772 十大功劳属 shi da gong lao shu Mahonia Nuttall, Gen. N. Amer. Pl. 1: 211. 1818.
  2. ^ "Mahonia Nutt". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 4 November 2023.
  3. ^ WFO (2023). "Mahonia Nutt". World Flora Online. Retrieved 4 November 2023.
  4. ^ Ackerfield, Jennifer (2015). Flora of Colorado (1st ed.). Fort Worth, Texas: BRIT Press. p. 201. ISBN 978-1-889878-45-4.
  5. ^ "Mahonia". Germplasm Resources Information Network. Agricultural Research Service, United States Department of Agriculture.
  6. ^ a b Yu, Chih-Chieh; Chung, Kuo-Fang (2017). "Why Mahonia? Molecular recircumscription of Berberis s.l., with the description of two new genera, Alloberberis and Moranothamnus". Taxon. 66 (6): 1371–1392. doi:10.12705/666.6.
  7. ^ Mahonia, USDA Natural Resources Conservation Service PLANTS Profile, 4 November 2023
  8. ^ Whittemore, Alan T. "Berberis". Flora of North America @ efloras.org. Retrieved 4 November 2023.
  9. ^ Loconte, H., & J. R. Estes. 1989. Phylogenetic systematics of Berberidaceae and Ranunculales (Magnoliidae). Systematic Botany 14:565-579.
  10. ^ Marroquín, Jorge S., & Joseph E. Laferrière. 1997. Transfer of specific and infraspecific taxa from Mahonia to Berberis. Journal of the Arizona-Nevada Academy of Science 30(1):53-55.
  11. ^ Laferrière, Joseph E. 1997. Transfer of specific and infraspecific taxa from Mahonia to Berberis. Botanicheskii Zhurnal 82(9):96-99.
  12. ^ Pabón-Mora, Natalia; González, Favio (2012). "Leaf development, metamorphic heteroblasty and heterophylly in Berberis s. l. (Berberidaceae)". The Botanical Review. 78 (4): 463–489. doi:10.1007/s12229-012-9107-2. S2CID 15401971.
  13. ^ Chen, Xiao-Hong; Xiang, Kun-Li; Lian, Lian; Peng, Huan-Wen; Erst, Andrey S.; Xiang, Xiao-Guo; Chen, Zhi-Duan; Wang, Wei (2020-10-01). "Biogeographic diversification of Mahonia (Berberidaceae): Implications for the origin and evolution of East Asian subtropical evergreen broadleaved forests". Molecular Phylogenetics and Evolution. 151: 106910. doi:10.1016/j.ympev.2020.106910. ISSN 1055-7903. PMID 32702526. S2CID 220731200.
  14. ^ RHS A-Z encyclopedia of garden plants. United Kingdom: Dorling Kindersley. 2008. p. 1136. ISBN 978-1405332965.
  15. ^ a b "Mahonia Oregon Grape, Hollyleaved barberry, Oregon Holly Grape, Oregon Holly". PFAF Plant Database. Plants for a Future, Registered Charity. 2010. Retrieved 4 November 2023.