Magnolia

This article refers to the botanical term. For other uses, see Magnolia (disambiguation).

Magnolia is a large genus of about 120 flowering plant species in the subfamily Magnolioideae of the family Magnoliaceae.

Magnolia species are mainly found in eastern North America, Central America and east and southeast Asia, although some are also found in South America.

The genus is named after Pierre Magnol, a botanist from Montpellier in France. The first species belonging to this genus to be identified was M. virginiana (Sweetbay magnolia), found by missionaries sent to North America in the 1680s. This was followed by M. grandiflora early in the 18th century, another North American plant.

Magnolia is an ancient genus. Having evolved before bees appeared, the flowers developed to encourage pollination by beetles. As a result, the carpels of Magnolia flowers are tough to avoid damage. Fossilised specimens of M. acuminata have been found dating to 20 million years ago, and of plants identifiably belonging to the Magnoliaceae back to 95 million years ago. Another primitive aspect of Magnolias are their lack of distinct sepals or petals. The term tepal has been coined to refer to the intermediate element that the Magnolia has instead.

Classification and selected species of Magnolia

• Magnolia subgenus Magnolia: Anthers open by splitting at the front facing the centre of the flower. Deciduous or evergreen. Flowers produced after the leaves.
  • Magnolia delavayi - Chinese evergreen magnolia
  • Magnolia fraseri - Fraser magnolia
  • Magnolia globosa -
  • Magnolia grandiflora - Southern magnolia
  • Magnolia macrophylla - Bigleaf magnolia
  • Magnolia nitida -
  • Magnolia obovata - Japanese bigleaf magnolia
  • Magnolia officinalis - Houpu magnolia
  • Magnolia sieboldii -
  • Magnolia tripetala - Umbrella tree
  • Magnolia virginiana - Sweetbay magnolia
  • Magnolia wilsonii - Wilson's magnolia
• Magnolia subgenus Yulania: Anthers open by splitting at the sides. Deciduous. Flowers mostly produced before leaves (except M. acuminata).
  • Magnolia acuminata - Cucumber tree
  • Magnolia amoena -
  • Magnolia biondii -
  • Magnolia campbellii - Campbell's magnolia
  • Magnolia cylindrica -
  • Magnolia dawsoniana -
  • Magnolia denudata - Yulan magnolia
  • Magnolia kobus - Kobushi magnolia
  • Magnolia liliiflora - Mulan magnolia
  • Magnolia salicifolia - Willow-leafed magnolia
  • Magnolia sargentiana -
  • Magnolia sprengeri -
  • Magnolia stellata - Star magnolia
  • Magnolia zenii -

Uses

In general, Magnolia is a genus which has attracted a lot of horticultural interest. Hybridisation has been immensely successful in combining the best aspects of different species to give plants which flower at an earlier age than the species themselves, as well as having more impressive flowers. One of the most popular garden magnolias is a hybrid, M. x soulangeana (Saucer magnolia; hybrid M. liliiflora x M. denudata).

The bark from M. officinalis has long been used in traditional Chinese medicine, where it is known as "houpu". In Japan, M. obvata has been used in a similar manner. The aromatic bark contains magnolol and honokiol, two polyphenolic compounds that have demonstrated anti-anxiety and anti-angiogenic properties. Magnolia bark also has been shown to reduce allergic and asthmatic reactions.

Two Magnolias: Magnolia_Nbr_2 Boston, Massachusetts, May, 2004

Reference

Hunt, D. (ed). 1998. Magnolias and their allies. International Dendrology Society & Magnolia Society.
ISBN 0-9517234-8-0