''Magnolia macrophylla'', the bigleaf magnolia, is a

deciduous In the fields of horticulture and botany, the term deciduous () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed Leaf, leaves, usually in the autumn; to the shedding of petals, aft ...

magnolia ''Magnolia'' is a large genus of about 210 to 340The number of species in the genus ''Magnolia'' depends on the taxonomic view that one takes up. Recent molecular and morphological research shows that former genera ''Talauma'', ''Dugandiodendr ...

native to the southeastern

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

and eastern

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

. This species boasts the largest simple

leaf A leaf (: leaves) is a principal appendage of the plant stem, stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leav ...

and single

flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

of any native plant in North America.

Classification

''Magnolia macrophylla'' has three subspecies; some botanists treat these plants as three separate

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

: *''Magnolia macrophylla'' subsp. ''macrophylla''. Bigleaf magnolia. Southeastern United States. Secure. Tree to 65-foot; leaves 20-35 inch long, fruit 1.5–4 inch long with more than 50 carpels. *''Magnolia macrophylla'' subsp. ''ashei'' (Wetherby) Spongberg. Ashe magnolia. Northwest

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

. Shrub or small tree to 40-foot; leaves 10–23 inch long, fruit 1.5–2.3 inch 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, Cloudforest magnolia, or ''eloxochitl.'' Mexico ( Hidalgo to

Oaxaca Oaxaca, officially the Free and Sovereign State of Oaxaca, is one of the 32 states that compose the political divisions of Mexico, Federative Entities of the Mexico, United Mexican States. It is divided into municipalities of Oaxaca, 570 munici ...

and

Veracruz Veracruz, formally Veracruz de Ignacio de la Llave, officially the Free and Sovereign State of Veracruz de Ignacio de la Llave, is one of the 31 states which, along with Mexico City, comprise the 32 Political divisions of Mexico, Federal Entit ...

, in

cloud forest A cloud forest, also called a water forest, primas forest, or tropical montane cloud forest, is a generally tropical or subtropical, evergreen, Montane forest, montane, Tropical and subtropical moist broadleaf forests, moist forest characteri ...

s). Tree to 65-foot; leaves 11–24 inch long, fruit 3–6 inch long with more than 70 carpels. Considered by some botanists to be a distinct species, '' Magnolia dealbata.''

Description

The bigleaf magnolia is a medium-sized understory

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, e.g., including only woody plants with secondary growth, only ...

50–65 feet tall. This species is distinguished from other magnolias by the large

size, 10–32 inch long and 4–35 inch broad. The largest leaf to be reported by a credible source is 3 ft 8 in (110 centimeters) in length. in addition to a petiole. The leaf's width can be up to . The tree's branches often bend under the weight of this heavy foliage. The flowers are typically six or nine-petaled (two or three whorls of three petals each, the larger ones with a dime-sized purple blotch at the base). The flower has as many as 580

stamens The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filamen ...

and is typically about wide, although there have been specimens as large as in width. It is the largest temperate (non-tropical) flower in the world. This, like all Magnolias, is beetle pollinated. The fruit is a cone-like cluster of achenes. The mature seeds, each covered with an orange

aril An aril (), also called arillus, is a specialized outgrowth from a seed that partly or completely covers the seed. An arillode, or false aril, is sometimes distinguished: whereas an aril grows from the attachment point of the seed to the ova ...

, hang down from the cone on silk-like threads. making themselves readily available to passing birds.

Bee Mortality

At the Arnold Arboretum, dead bees have been observed inside Bigleaf magnolia flowers. However the bees in cited article are honeybees which are not native to North America.

Distribution and habitat

Bigleaf magnolia is found in rich mesic 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 Appalachia ( ) is a geographic region located in the Appalachian Mountains#Regions, central and southern sections of the Appalachian Mountains in the east of North America. In the north, its boundaries stretch from the western Catskill Mountai ...

, the '' Fraser magnolia.'' The Ashe magnolia is a rare

shrub A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple ...

, exceptionally a small tree, that is found only along the bluffs and ravines adjacent to the

Apalachicola River The Apalachicola River is a river, approximately long, in the state of Florida. The river's large drainage basin, watershed, known as the ACF River Basin, Apalachicola, Chattahoochee and Flint (ACF) River Basin, drains an area of approximately ...

, 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

s, and longer

fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

s. The 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 may refer to: Food * Diet (nutrition), the sum of the food consumed by an organism or group * Dieting, the deliberate selection of food to control body weight or nutrient intake ** Diet food, foods that aid in creating a diet for weight loss ...

. In the southeastern United States, especially

Alabama Alabama ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South, Deep Southern regions of the United States. It borders Tennessee to the north, Georgia (U.S. state), Georgia to the east, Florida and the Gu ...

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 density Population density (in agriculture: Standing stock (disambiguation), standing stock or plant density) is a measurement of population per unit land area. It is mostly applied to humans, but sometimes to other living organisms too. It is a key geog ...

, and high collection pressure can extirpate this species locally. Bigleaf magnolia is listed as

threatened A threatened species is any species (including animals, plants and fungi) which is vulnerable to extinction in the near future. Species that are threatened are sometimes characterised by the population dynamics measure of ''critical depensatio ...

North Carolina North Carolina ( ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, South Carolina to the south, Georgia (U.S. stat ...

and

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching, inv ...

Arkansas Arkansas ( ) is a landlocked state in the West South Central region of the Southern United States. It borders Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, Texas to the southwest, and Oklahoma ...

and

Ohio Ohio ( ) is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Lake Erie to the north, Pennsylvania to the east, West Virginia to the southeast, Kentucky to the southwest, Indiana to the ...

. The Florida Department of Agriculture lists the Ashe magnolia as

, due to its small population and restricted range. The Mexican bigleaf magnolia is also endangered, by loss of habitat.

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 moist, well-drained soil and a low pH. This tree will likely succeed in sites that closely mimic its natural habitat and where it is protected from strong wind that can tatter its large foliage. It can be grown farther north than its southerly range suggests, but needs watering during extended dry periods. This plant is generally problem-free.

Gallery

File:Bigleaf Magnolia Magnolia macrophylla Leaf 2500px.jpg, A single large leaf File:Bigleaf Magnolia Magnolia macrophylla Sapling 1550px.jpg, A sapling File:Magnolia macrophylla bigleaf magnolia.JPG, Naturalized tree File:Magnolia macrophyla ssp. ashei flower.jpg, ''Magnolia macrophylla'' ssp. ''ashei'' open flower File:Magnolia macrophyla ssp. ashei fruit.jpg, ''Magnolia macrophylla'' ssp. ''ashei'' mature fruit File:Magnolia macrophylla ssp. ashei.jpg, ''Magnolia macrophylla'' ssp. ''ashei'' flower detail File:Magnolia macrophylla ssp. macrophylla flower.jpg, ''Magnolia macrophylla'' ssp. ''macrophylla'' open flower File:Magnolia macrophylla ssp. macrophylla fruit.jpg, ''Magnolia macrophylla'' ssp. ''macrophylla'' mature fruit File:Magnolia macrophylla ssp. macrophylla.jpg, ''Magnolia macrophylla'' ssp. ''macrophylla'' bud break File:Magnolia macrophylla tree AA.jpg, ''Magnolia macrophylla'' ssp. ''macrophylla'' 1989 accession (#960-89*A), Arnold Arboretum of Harvard University File:Magnolia macrophylla ssp. macrophylla leaves.jpg, ''Magnolia macrophylla'' ssp. ''macrophylla'' leaves in fall File:MagnoliamacrophyllaNCS.jpg, Large ''M. macrophylla'' ssp. ''macrophylla'' specimen growing on NCSU campus. File:BigLeafMagnoliaFruitUnripe.jpg, An unripe fruit. File:BigleafMagnoliaHighline.jpg, A northerly specimen located on NYC's Highline.

References

External links

''Magnolia macrophylla'' images at the Arnold Arboretum of Harvard University Plant Image Database
*Hetman, Jon
"Magnolia macrophylla".
Arnold Arboretum of Harvard University website, 13 May 2019. Accessed 20 April 2020. *Friedman, William (Ned
"Killer magnolias".
'Posts from the Collections,'' Arnold Arboretum of Harvard University website, 20 July 2019. Accessed 20 April 2020.

* ttps://web.archive.org/web/20080604141716/http://www.cas.vanderbilt.edu/bioimages/species/frame/mama2.htm ''Magnolia macrophylla'' images at bioimages.vanderbilt.edubr>Field Guide to the Rare Plants and Animals of Florida Online: Magnolia asheiInteractive Distribution Map of ''Magnolia macrophylla''
{{Taxonbar, from=Q1093540 Magnolia, macrophylla Endangered flora of the United States Trees of Northern America Garden plants of North America Ornamental trees