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Family: Magnoliaceae
Description: There are about 75 species in the Magnolia genus. They are distributed in S.E. Asia, and from Venezuela to the Eastern U.S. Eight of these occur in the Southeastern United States. Duncan & Duncan describe the genus as follows, "Recognized by leaf margin entire, some species having blades without lobes and some with base eared or heart-shaped. Trees or shrubs. Pith continuous, but often with firm diaphragms. Buds covered by two fused stipules. Perianth of 9-18 segments, the sepal usually difficult to distinguish from petals. Each flower with stamens and pistils, the latter obviously arranged spirally in a cone-shaped structure. Fruits conelike, an aggregate of leathery follicles, each formed from a single pistil and bearing 1 or 2 seeds that, when released, usually hang for some time on a long threadlike stalk"(Duncan et al.,1988). As described by the Staff of the L.H. Bailey Hortorium at Cornell University, the leaves are alternate and often leathery. The flowers are terminal, solitary, large, and often showy (Staff et al.,1976).
Species List: The following eight species of Magnolia are listed by Duncan & Duncan as occuring in the Southeast. The species name is followed by the common name. (Duncan et al.,1988)
*Callaway lists pyramidata as a variety of M. fraseri, not as a seperate species; also ashei as a variety of M. macrophylla instead of a seperate species (Callaway,1994).
For a more complete listing of Magnolia species click here.
Identification Guide: Following is an identification key showing defining characteristics for these eight species of Magnolia(Duncan et al., 1988)..
I. Leaves acuminate to slightly cordate at base
A. Leaves glaucous beneath, aromatic, petals usually
less than 5cm long.....M. virginia
B. Leaves green or rusty beneath, not aromatic, petals
usually more than 5cm long
1) Leaves evergreen, coriaceous.....M. grandiflora
2) Leaves deciduous, membranous
a) Most leaves clustered terminally on twig.....M. tripetala
b) Leaves scattered along twig.....M. acuminata
II. Leaves deeply cordate or eared at base
A. Buds and twigs hairy, leaves white beneath
1) Trunk upright, stamens 15-18mm long, conelike fruits
subglobose to globose.....M. macrophylla
2) Trunk usually not strickly upright, stamens 11-13mm long,
conelike fruits subcylindric to ovoid.....M. ashei
B. Buds and twigs glabrous, leaves green below
1) Stamens 8-15mm long, most leaves over 25cm long, conelike
fruits 6.5-11cm long.....M. fraseri
2) Stamens 4-6mm long, most leaves less than 25cm long, conelike
fruits 3.5-5.5cm long.....M. pyramidata
General Information: Magnolia was named for Pierre Magnol (1638-1715), a French professor of botany at Montpelier (Jackson, 1996). This genus of evergreen or deciduous trees or shrubs is primarily distributed in warm temperate to tropical regions, and don't like dry or sterile soil. They are frequently grown for ornamental purposes because of their often showy and fragrant flowers. The North American natives bloom in early summer after the leaves expand. Many of the Asian species bloom in early spring on naked twigs (Elias, 1980). The seeds are eaten by wildlife, especially birds (Duncan et al.,1988). Pollination is facilitated for the most part by beetles feeding in the flowers (Callaway, 1994).