Genus: Magnolia

Magnolia macrophylla L.

Common name: Bigleaf Magnolia
(Odenwald and Turner, 1996)

Other Common names: Cowcumber Magnolia (Odenwald and Turner, 1996)
Great-Leaved Magnolia (Gray, 1864)
Silver-leaf and Big-Bloom (Small, 1933)

Ruth Ann Pannell, Biology Major

Franklin College of Arts and Sciences
University of Georgia, Athens
(Go Dawgs!)

Taxonomic Arrangement of Magnolia macrophylla (Milne and Milne, 1975) (Hardin, 1992) :

Class: Magnoliopsida
SubClass: Magnolidae
Order: Ranales
Family: Magnoliaceae
Genus: Magnolia
Species: macrophylla

Description of Magnolia macrophylla

Magnolia macrophylla is a medium sized tree which has a max trunk diameter of 8-10 feet (Small, 1933) and a maximum height of 50 feet (Wyman, 1951) .


This tree has the largest simple tree leaf of any dictotyledonous tree in North America. The leaves are "deciduous, simple, alternate; blades cordate or lobed at the base, 20-30" long; upper surfaces glabrous, dark green; lower surfaces flaucous, pubescent" (Brown and Kirman, 1990) . Leaves are thin, "blue-gray-bloomy beneath and sometimes more than 2 feet long" (Kelly, 1995)

Leaves of Magnolia macrophylla
Courtesy of UGA Herbarium


"Stout, brittle, densely tomentose when young; terminal winter buds bluntly pointed, flattened, covered wiath white hairs, 1 3/4 - 2" long; a large pith" (Brown and Kirman, 1990).


Beautiful, ivory flowers growing 10 to 15 inches wide, "with three purple blotches on inner petals." Blooms in April and May, "after foliage in upper canopy in center of a large foliage cluster. Fragrant" (Odenwald and Turner, 1996) . The flowers are impresive but have a disagreeable odor (Everett, 1968) .

Flower of Magnolia macrophylla
Courtesy of UGA Herbarium


Cone-like aggregate of follicles, "ovoid to subglobose, reddish purple, soon blackening. Seeds bright red." Mature in July and August (Odenwald and Turner, 1996) .
Cone of Magnolia macrophylla
Slide from UGA Herbarium


The bark is thin and gray. It forms "small inconspicuous plates on older trees" (Brown and Kirman, 1990) .


"Dense, upright, pyrimidal form in sunlight for first 15 to 20 years becoming more irregular with advanced age. Loose open density in shade" (Odenwald and Turner, 1996) . The trunk is sometimes branched at the base (Small, 1933) .


Magnolia macrophyllawas described by Michaux (Radford, 1968) . The genus Magnolia was named by Linnaeus in honor of Pierre Magnol, who was the physician of King Louis XIV of France and was the director of a botanical garden at Montpellier (Grimm, 1967) . Magnol was also a professor of Botany at Montpellier (Gray, 1864) .

Scientific Reference with Identification Key:

Radford, A.E., H.E. ahles and C.R. Bell. 1968. Manual of the Vascular Flora of the Carolinas. University of North Carolina Press. Chapel Hill, NC. (ISBN 0-8078-1087-8)

Where to find this Species:

Magnolia macrophylla occurs in rich wooded ravines in isolated populations. It occurs in the Piedmont and upper Coastal Plain of western Georgia (Brown and Kirman, 1990).

Species Distribution Chart

Magnolia macrophylla L.

North America:
Continental United States; Canada
Yes Duncan and Duncan, 1988
Eastern North America:
United States east of Mississippi;
Ontario and eastern Canada
YesDuncan and Duncan, 1988
Southeastern United States:
YesDuncan and Duncan, 1988.
Southern Appalachian States:
YesDuncan and Duncan, 1988
Coastal PlainIsolated PopulationsBrown and Kirman, 1990
PiedmontIsolated PopulationsBrown and Kirman, 1990
Blue Ridge MountainsIsolated PopulationsBrown and Kirman, 1990
Great Smoky Mountains National Park
YesBrown and Kirman, 1990
Ridge and ValleyYesDuncan and Duncan, 1988
Cumberland PlateauMarginalBrown and Kirman, 1990
Central ArchNoBrown and Kirman, 1990
GeorgiaIsolated PopulationDuncan and Duncan, 1988
Clarke County, GeorgiaNoJones and Coile, 1979
Sams FarmNoJones and Coile, 1979
Old Field
NoJones and Coile, 1979
NoJones and Coile, 1979
NoJones and Coile, 1979
1-Hectare Plot
NoRuthie Pannell, pers. Ob.

Other Information about Magnolia macrophylla:

Man with flower of Magnolia macrophylla
Slide courtesy of UGA Herbarium

Magnolia macrophylla is considered by many to be the most spectacular deciduous tree in the Southeastern United States because is has such large leaves and stands out to any observer. It is a medium sized tree and primarily an understory specimen in it's native habitat. Magnolia macrophylla has a slow to moderate growth rate. It performs best in loose, moist, well-drained soil (Odenwald and Turner, 1996) . Magnolia macrophylla requires acid soil and protection from the wind (Kelly, 1995) . If trying to grow Magnolia macrophylla it should be placed in a protected position because of it's frail leaves (Odenwald and Turner, 1996) .

Magnolia macrophylla bloom in Aptil and May. It's fruits mature in July and August (Odenwald and Turner, 1996) . Magnolia macrophylla is not a long lived tree and typically does not live over 40 years (Kelly, 1995) .
Magnolia macrophylla is hard to grow because it is a highly tempermental tree. It is hard to establish and should be enjoyed in its natural environment. It may be more easily established on old, undisturbed habitats with rich woodland soils (Odenwald and Turner, 1996) . Some magnificent sixty to seventy-five foot specimens of Magnolia macrophylla exist on bluffs along trails at Gloster Arboretum, Gloster, Mississippi (Odenwald and Turner, 1996)


Magnolia macrophylla has little economic importance or uses because of it's rarity. It is not used often as an ornamental tree because its foilage is so frail (Duncan and Duncan, 1988) .

How to Encounter Magnolia macrophylla

Magnolia macrophylla can be found in its native range in the US from Kentucky to Florida to Louisiana (Odenwald and Turner, 1996) . It is found in bottomland woods, wooded ravines, and rich wooded slopes (Duncan and Duncan, 1996) . Although no specimens are found in Clarke County the largest specimens of this species can be found on bluffs and along the trails of Gloster Arboretum, in Gloster, Mississippi (Odenwald and Turner, 1996) .

How to distinguish Magnolia macrophylla from other Taxa:

Magnolia macrophylla can easily be recognized by its large leaves which are the largest of any native tree in temperate North America (Wyman, 1951) . The leaves can reach over 2 feet long (Everett, 1968).

Useful Links for furthur study of Magnolia macrophylla