Bigleaf magnolia
Encyclopedia
Magnolia macrophylla, the bigleaf magnolia, is a deciduous
magnolia
native to the southeastern United States
and eastern Mexico
. This species boasts the largest simple leaf
and single flower
of any native plant in North America.
Magnolia macrophylla has three subspecies; some botanists treat these plants as three separate species
:
15-20 m tall, though some individuals over 27m tall (and over 100cm circumference) have been documented by the Eastern Native Tree Society. This species is distinguished from other magnolias by the large leaf
size, 25-80 cm long and 11-30 cm broad. The tree's branches often bend under the weight of this heavy foliage.
woods; any disturbance that lets more light reach the ground is beneficial to the establishment of bigleaf magnolia, but despite its relatively fast growth-rate when stimulated by more light, other understory and canopy trees/seedlings are usually able to outgrow and out-compete it. This suits the plant just fine as it is tolerant of low light levels; it does not need full sun to survive once established (however, it does not tolerate full shade). Natural regeneration is quite limited due to the scarcity of mature, seed-bearing plants and the fact that this tree's population mostly consists of widely scattered individuals. In addition, this species is plagued by poor seed set (most likely from limiting factors mentioned above) and low seed viability
, a trait shared by its cousin and frequent associate in the wild in Appalachia
, the Fraser magnolia.
The Ashe magnolia is a rare shrub
, exceptionally a small tree, that is found only along the bluffs and ravines adjacent to the Apalachicola River
in Florida
, along with several other rare plants unique to the area, such as Florida Yew
and Florida torreya
. It resembles the typical subsp. macrophylla, but has shorter, broader leaves, smaller flower
s, and longer fruit
s. The 6 to 8 in (152.4 to 203.2 mm) flowers bloom in late spring, and are white with rose-purple blotches on the inner tepals. The fruit is eaten by wildlife, but because of the plant's scarceness, it does not form a significant portion of any creature's diet
.
In the southeastern United States, especially Alabama
and surrounding areas, Magnolia macrophylla is sometimes called the "cowcumber magnolia," in contrast with the much smaller-leaved cucumber-tree magnolia, M. acuminata.
, and high collection
pressure can extirpate this species locally. Bigleaf magnolia is listed as endangered in Arkansas
and Ohio
. The Florida Department of Agriculture lists the Ashe magnolia as endangered, due to its small population and restricted range.
Deciduous
Deciduous means "falling off at maturity" or "tending to fall off", and is typically used in reference to trees or shrubs that lose their leaves seasonally, and to the shedding of other plant structures such as petals after flowering or fruit when ripe...
magnolia
Magnolia
Magnolia is a large genus of about 210 flowering plant species in the subfamily Magnolioideae of the family Magnoliaceae. It is named after French botanist Pierre Magnol....
native to the southeastern United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
and eastern Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
. This species boasts the largest simple leaf
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
and single flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
of any native plant in North America.
Classification
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
:
- Magnolia macrophylla subsp. macrophylla. Bigleaf magnolia. Southeastern United States. Secure. Tree to 20 m; leaves 50-90 cm long, fruit 4-10 cm long with more than 50 carpels.
- Magnolia macrophylla subsp. ashei (Wetherby) Spongberg. Ashe magnolia. Northwest FloridaFloridaFlorida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
. Shrub or small tree to 12 m; leaves 25-60 cm long, fruit 4-5 cm long with less than 50 carpels. Considered by some botanists to be a distinct species, Magnolia ashei.
- Magnolia macrophylla subsp. dealbata (Zuccarini) J. D. Tobe. Mexican bigleaf magnolia or Cloudforest magnolia. Mexico (Hidalgo to OaxacaOaxacaOaxaca , , officially Estado Libre y Soberano de Oaxaca is one of the 31 states which, along with the Federal District, comprise the 32 federative entities of Mexico. It is divided into 571 municipalities; of which 418 are governed by the system of customs and traditions...
and VeracruzVeracruzVeracruz, formally Veracruz de Ignacio de la Llave officially Estado Libre y Soberano de Veracruz de Ignacio de la Llave , is one of the 31 states that, along with the Federal District, comprise the 32 federative entities of Mexico. It is divided in 212 municipalities and its capital city is...
, in cloud forestCloud forestA cloud forest, also called a fog forest, is a generally tropical or subtropical evergreen montane moist forest characterized by a persistent, frequent or seasonal low-level cloud cover, usually at the canopy level. Cloud forests often exhibit an abundance of mosses covering the ground and...
s). Tree to 20 m; leaves 30-60 cm long, fruit 8-15 cm long with more than 70 carpels. Considered by some botanists to be a distinct species, Magnolia dealbata.
Description
Bigleaf magnolia is medium-sized understory treeTree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
15-20 m tall, though some individuals over 27m tall (and over 100cm circumference) have been documented by the Eastern Native Tree Society. This species is distinguished from other magnolias by the large leaf
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
size, 25-80 cm long and 11-30 cm broad. The tree's branches often bend under the weight of this heavy foliage.
Distribution and habitat
Bigleaf magnolia is found in rich mesicMesic habitat
In ecology, a mesic habitat is a type of habitat with a moderate or well-balanced supply of moisture, e.g., a mesic forest, a temperate hardwood forest, or dry-mesic prairie. Compared to a dry habitat, a mesic habitat is moister....
woods; any disturbance that lets more light reach the ground is beneficial to the establishment of bigleaf magnolia, but despite its relatively fast growth-rate when stimulated by more light, other understory and canopy trees/seedlings are usually able to outgrow and out-compete it. This suits the plant just fine as it is tolerant of low light levels; it does not need full sun to survive once established (however, it does not tolerate full shade). Natural regeneration is quite limited due to the scarcity of mature, seed-bearing plants and the fact that this tree's population mostly consists of widely scattered individuals. In addition, this species is plagued by poor seed set (most likely from limiting factors mentioned above) and low seed viability
Viability
Viable or viability is the ability of a thing to maintain itself or recover its potentialities.Viable or viability may also refer to:...
, a trait shared by its cousin and frequent associate in the wild in Appalachia
Appalachia
Appalachia is a term used to describe a cultural region in the eastern United States that stretches from the Southern Tier of New York state to northern Alabama, Mississippi, and Georgia. While the Appalachian Mountains stretch from Belle Isle in Canada to Cheaha Mountain in the U.S...
, the Fraser magnolia.
The Ashe magnolia is a rare shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
, exceptionally a small tree, that is found only along the bluffs and ravines adjacent to the Apalachicola River
Apalachicola River
The Apalachicola River is a river, approximately 112 mi long in the State of Florida. This river's large watershed, known as the ACF River Basin for short, drains an area of approximately into the Gulf of Mexico. The distance to its farthest headstream in northeast Georgia is approximately 500...
in Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
, along with several other rare plants unique to the area, such as Florida Yew
Taxus floridana
Taxus floridana is a species of yew, found only in a small area of under 10 km² on the eastern side of the Apalachicola River in northern Florida at altitudes of 15–30 m. It is listed as an endangered species.-Description:...
and Florida torreya
Torreya taxifolia
Torreya taxifolia, commonly known as the Florida torreya, gopher wood, stinking yew, or stinking cedar , is a rare and endangered species found in the Southeastern United States, at the state border region of northern Florida and southwestern Georgia.It is the type species of the genus Torreya...
. It resembles the typical subsp. macrophylla, but has shorter, broader leaves, smaller flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s, and longer fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
s. The 6 to 8 in (152.4 to 203.2 mm) flowers bloom in late spring, and are white with rose-purple blotches on the inner tepals. The fruit is eaten by wildlife, but because of the plant's scarceness, it does not form a significant portion of any creature's diet
Diet (nutrition)
In nutrition, diet is the sum of food consumed by a person or other organism. Dietary habits are the habitual decisions an individual or culture makes when choosing what foods to eat. With the word diet, it is often implied the use of specific intake of nutrition for health or weight-management...
.
In the southeastern United States, especially Alabama
Alabama
Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...
and surrounding areas, Magnolia macrophylla is sometimes called the "cowcumber magnolia," in contrast with the much smaller-leaved cucumber-tree magnolia, M. acuminata.
Threats
Collection, both legal and illegal, may have an adverse impact on this tree's population due to low population densityPopulation density
Population density is a measurement of population per unit area or unit volume. It is frequently applied to living organisms, and particularly to humans...
, and high collection
Collecting
The hobby of collecting includes seeking, locating, acquiring, organizing, cataloging, displaying, storing, and maintaining whatever items are of interest to the individual collector. Some collectors are generalists, accumulating merchandise, or stamps from all countries of the world...
pressure can extirpate this species locally. Bigleaf magnolia is listed as endangered in Arkansas
Arkansas
Arkansas is a state located in the southern region of the United States. Its name is an Algonquian name of the Quapaw Indians. Arkansas shares borders with six states , and its eastern border is largely defined by the Mississippi River...
and Ohio
Ohio
Ohio is a Midwestern state in the United States. The 34th largest state by area in the U.S.,it is the 7th‑most populous with over 11.5 million residents, containing several major American cities and seven metropolitan areas with populations of 500,000 or more.The state's capital is Columbus...
. The Florida Department of Agriculture lists the Ashe magnolia as endangered, due to its small population and restricted range.
Cultivation
Bigleaf magnolia is often short-lived under cultivation unless its rather demanding requirements are met. This tree likes loose, undisturbed rich mesic soil (or mulch and compost substitutes) in full sun or part shade with plenty of moisture. This tree will likely succeed in sites that closely mimic its natural habitat and where it is protected from strong wind which can tatter its large foliage. It can be grown farther north than its southernly range suggests, but needs watering during extended dry periods. This plant is generally problem free.External links
- An ecological study of Magnolia macrophylla in Gaston County, NC
- Magnolia macrophylla images at bioimages.vanderbilt.edu
- Field Guide to the Rare Plants and Animals of Florida Online: Magnolia ashei
- Magnolia macrophylla Distribution Map
- Interactive Distribution Map of Magnolia macrophylla
- http://www.ents-bbs.org/viewtopic.php?f=73&t=2133