The

native Native may refer to: People * Jus soli, citizenship by right of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Native Americans (disambiguation) In arts and entert ...

flora Flora is all the plant life present in a particular region or time, generally the naturally occurring (indigenous (ecology), indigenous) native plant, native plants. Sometimes bacteria and fungi are also referred to as flora, as in the terms '' ...

of the United States includes about 17,000

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

vascular plants Vascular plants (), also called tracheophytes () or collectively Tracheophyta (), form a large group of land plants ( accepted known species) that have lignified tissues (the xylem) for conducting water and minerals throughout the plant. They ...

, plus tens of thousands of additional species of other

plant Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclu ...

s and plant-like

organisms In biology, an organism () is any life, living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy (biology), taxonomy into groups such as Multicellular o ...

such as

alga Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

e, lichens and other

fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...

, and mosses. About 3,800 additional non-native species of vascular plants are recorded as established outside of cultivation in the U.S., as well as a much smaller number of non-native non-vascular plants and plant relatives. The United States possesses one of the most diverse temperate floras in the world, comparable only to that of China. Several

biogeographic Biogeography is the study of the distribution of species and ecosystems in geographic space and through geological time. Organisms and biological communities often vary in a regular fashion along geographic gradients of latitude, elevation, ...

factors contribute to the richness and diversity of the U.S. flora. While most of the United States has a

temperate In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout ...

climate Climate is the long-term weather pattern in an area, typically averaged over 30 years. More rigorously, it is the mean and variability of meteorological variables over a time spanning from months to millions of years. Some of the meteorologi ...

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S. ...

has vast

arctic The Arctic ( or ) is a polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenland), Finland, Iceland, N ...

areas, the southern part of

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

is tropical, as well as

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only state ...

(including high mountains), and the

U.S. territories Territories of the United States are sub-national administrative divisions overseen by the federal government of the United States. The various American territories differ from the U.S. states and tribal reservations as they are not sover ...

in the Caribbean and the Pacific, and alpine summits are present on many western mountains, as well as a few in the Northeast. The U.S.

coastline The coast, also known as the coastline or seashore, is defined as the area where land meets the ocean, or as a line that forms the boundary between the land and the coastline. The Earth has around of coastline. Coasts are important zones in ...

borders three oceans: The

Atlantic The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe an ...

(and

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...

), the

Arctic The Arctic ( or ) is a polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenland), Finland, Iceland, N ...

, and the

Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contine ...

. Finally, the U.S. shares long borders with Canada and Mexico, and is relatively close to the

Bahamas The Bahamas (), officially the Commonwealth of The Bahamas, is an island country within the Lucayan Archipelago of the West Indies in the North Atlantic. It takes up 97% of the Lucayan Archipelago's land area and is home to 88% of the ar ...

Cuba Cuba ( , ), officially the Republic of Cuba ( es, República de Cuba, links=no ), is an island country comprising the island of Cuba, as well as Isla de la Juventud and several minor archipelagos. Cuba is located where the northern Caribbea ...

and other Caribbean islands, and easternmost Asia. There are also rainforests as well as some of the driest deserts in the world. The native flora of the United States has provided the world with a large number of

horticultural Horticulture is the branch of agriculture that deals with the art, science, technology, and business of plant cultivation. It includes the cultivation of fruits, vegetables, nuts, seeds, herbs, sprouts, mushrooms, algae, flowers, seaweeds and no ...

and agricultural plants, mostly

ornamentals Ornamental plants or garden plants are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars that i ...

, such as

flowering dogwood ''Cornus florida'', the flowering dogwood, is a species of flowering tree in the family Cornaceae native to eastern North America and northern Mexico. An endemic population once spanned from southernmost coastal Maine south to northern Florida ...

redbud ''Cercis'' is a genus of about 10 species in the subfamily Cercidoideae of the pea family Fabaceae, native to warm temperate regions. It contains small deciduous trees or large shrubs commonly known as redbuds. They are characterised by si ...

, mountain laurel,

bald cypress ''Taxodium distichum'' (bald cypress, swamp cypress; french: cyprès chauve; ''cipre'' in Louisiana) is a deciduous conifer in the family Cupressaceae. It is native to the southeastern United States. Hardy and tough, this tree adapts to a wide ...

southern magnolia ''Magnolia grandiflora'', commonly known as the southern magnolia or bull bay, is a tree of the family Magnoliaceae native to the Southeastern United States, from Virginia to central Florida, and west to East Texas. Reaching in height, it is ...

, and

black locust ''Robinia pseudoacacia'', commonly known in its native territory as black locust, is a medium-sized hardwood deciduous tree, belonging to the tribe Robinieae of the legume family Fabaceae. It is endemic to a few small areas of the United States ...

, all now cultivated in temperate regions worldwide, but also various food plants such as blueberries,

black raspberries Black raspberry is a common name for three species of the genus ''Rubus'': *''Rubus leucodermis'', native to western North America *''Rubus occidentalis ''Rubus occidentalis'' is a species of ''Rubus'' native to eastern North America. Its co ...

cranberries Cranberries are a group of evergreen dwarf shrubs or trailing vines in the subgenus ''Oxycoccus'' of the genus ''Vaccinium''. In Britain, cranberry may refer to the native species ''Vaccinium oxycoccos'', while in North America, cranberry ...

, maple syrup and sugar, and

pecan The pecan (''Carya illinoinensis'') is a species of hickory native to the southern United States and northern Mexico in the region of the Mississippi River. The tree is cultivated for its seed in the southern United States, primarily in Georgia, ...

s, and

Monterey pine ''Pinus radiata'' ( syn. ''Pinus insignis''), the Monterey pine, insignis pine or radiata pine, is a species of pine native to the Central Coast of California and Mexico ( Guadalupe Island and Cedros island). It is an evergreen conifer in the f ...

and other timber trees. Some of the native U.S. plants, such as '' Franklinia alatamaha,'' have demonstrably become extinct or extinct in the wild; others, such as ''

Micranthemum micranthemoides ''Hemianthus micranthemoides'', also known as Micranthemum micranthemoides, pearl grass and pearl weed, is a popular aquatic plant most commonly used in aquascaping Aquascaping is the craft of arranging aquatic plants, as well as rocks, stone ...

'', have not been seen in decades, but may still be extant. Thousands of other native U.S. vascular plants are considered rare, threatened, or endangered, either globally (rangewide) or within particular states.

Divisions

According to Armen Takhtajan, Robert F. Thorne, and other geobotanists, the territory of the United States (including

and

) is divided between three

floristic kingdom A phytochorion, in phytogeography, is a geographic area with a relatively uniform composition of plant species. Adjacent phytochoria do not usually have a sharp boundary, but rather a soft one, a transitional area in which many species from both re ...

s, six

floristic region A phytochorion, in phytogeography, is a geographic area with a relatively uniform composition of plant species. Adjacent phytochoria do not usually have a sharp boundary, but rather a soft one, a transitional area in which many species from both r ...

s and twelve

floristic province A phytochorion, in phytogeography, is a geographic area with a relatively uniform composition of plant species. Adjacent phytochoria do not usually have a sharp boundary, but rather a soft one, a transitional area in which many species from both r ...

s, characterized by a certain degree of

endemism Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

: :

Holarctic Kingdom The asterisk ( ), from Late Latin , from Ancient Greek , ''asteriskos'', "little star", is a typographical symbol. It is so called because it resembles a conventional image of a heraldic star. Computer scientists and mathematicians often voc ...

Circumboreal Region The Circumboreal Region in phytogeography is a floristic region within the Holarctic Kingdom in Eurasia and North America, as delineated by such geobotanists as Josias Braun-Blanquet and Armen Takhtajan. It is the largest floristic region i ...

::: Arctic Province ::: Canadian Province ::

North American Atlantic Region North American Atlantic Region is a floristic region within the Holarctic Kingdom identified by Armen Takhtajan and Robert F. Thorne, spanning from the Atlantic and Gulf coasts to the Great Plains and comprising a major part of the United States ...

::: Appalachian Province ::: Atlantic and Gulf Coastal Plain Province ::: North American Prairies Province :: Rocky Mountain Region ::: Vancouverian Province ::: Rocky Mountain Province ::

Madrean Region The Madrean Region (named after the Sierra Madre Occidental) is a floristic region within the Holarctic Kingdom in North America, as delineated by Armen Takhtajan and Robert F. Thorne. It occupies arid or semiarid areas in the southwestern Unite ...

::: Great Basin Province ::: Californian Province :::

Sonoran Province The Madrean Region (named after the Sierra Madre Occidental) is a floristic region within the Holarctic Kingdom in North America, as delineated by Armen Takhtajan and Robert F. Thorne. It occupies arid or semiarid areas in the southwestern United ...

: Neotropical Kingdom ::

Caribbean Region The Caribbean region of Colombia or Caribbean coast region is in the north of Colombia and is mainly composed of 8 departments located contiguous to the Caribbean.West Indian Province West or Occident is one of the four cardinal directions or points of the compass. It is the opposite direction from east and is the direction in which the Sun sets on the Earth. Etymology The word "west" is a Germanic word passed into some R ...

: Paleotropic Kingdom :: Hawaiian Region :::

Hawaiian Province Hawaiian may refer to: * Native Hawaiians, the current term for the indigenous people of the Hawaiian Islands or their descendants * Hawaii state residents, regardless of ancestry (only used outside of Hawaii) * Hawaiian language Historic uses * ...

Some prominent botanists who have studied and published on U.S. flora

John Clayton John Clayton may refer to: Arts and entertainment Writing *John Clayton (architect) (died 1861), English architect and writer *John Bell Clayton and Martha Clayton, John Bell Clayton (c. 1907–1955), American writer *John Clayton (sportswriter) ( ...

(1694–1773) * John Bartram (1699–1777) *

Carl Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his Nobility#Ennoblement, ennoblement in 1761 as Carl von Linné#Blunt, Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalise ...

(1707–1778) *

Peter Kalm Pehr Kalm (6 March 1716 – 16 November 1779), also known as Peter Kalm, was a Swedish explorer, botanist, naturalist, and agricultural economist. He was one of the most important apostles of Carl Linnaeus. In 1747, he was commissioned by the ...

(1716–1779) * William Bartram (1739–1823) *

André Michaux André Michaux, also styled Andrew Michaud, (8 March 174611 October 1802) was a French botanist and explorer. He is most noted for his study of North American flora. In addition Michaux collected specimens in England, Spain, France, and even Per ...

(1746–1802) *

William Clark William Clark (August 1, 1770 – September 1, 1838) was an American explorer, soldier, Indian agent, and territorial governor. A native of Virginia, he grew up in pre-statehood Kentucky before later settling in what became the state of Miss ...

(1770–1838) * Meriwether Lewis (1774–1809) *

Frederick Traugott Pursh Frederick Traugott Pursh (or Friedrich Traugott Pursch) (February 4, 1774 – July 11, 1820) was a German–American botanist. Born in Großenhain, Saxony, under the name Friedrich Traugott Pursh, he was educated at Dresden Botanical Gardens, a ...

(1774–1820) * Alphonse Louis Pierre Pyramus de Candolle (1778–1841) * Constantine Samuel Rafinesque (1783–1840) *

Thomas Nuttall Thomas Nuttall (5 January 1786 – 10 September 1859) was an English botanist and zoologist who lived and worked in America from 1808 until 1841. Nuttall was born in the village of Long Preston, near Settle in the West Riding of Yorkshire and ...

(1786–1859) * John Torrey (1796–1873) * George Engelmann (1809–1884) * Asa Gray (1810–1888) * George Vasey (1822–1893) *

Sereno Watson Sereno Watson (December 1, 1826 in East Windsor Hill, Connecticut – March 9, 1892 in Cambridge, Massachusetts) was an American botanist. Graduating from Yale in 1847 in Biology, he drifted through various occupations until, in California, he j ...

(1826–1892) *

Charles Sprague Sargent Charles Sprague Sargent (April 24, 1841 – March 22, 1927) was an American botanist. He was appointed in 1872 as the first director of Harvard University's Arnold Arboretum in Boston, Massachusetts, and held the post until his death. He pub ...

(1841–1927) *

Edward Lee Greene Edward Lee Greene (August 20, 1843–November 10, 1915) was an American botanist known for his numerous publications including the two-part ''Landmarks of Botanical History'' and the describing of over 4,400 species of plants in the American W ...

(1843–1915) *

John Merle Coulter John Merle Coulter, Ph. D. (November 20, 1851 – December 23, 1928) was an American botanist and educator. In his career in education administration, Coulter is notable for serving as the president of Indiana University and Lake Forest College a ...

(1851–1928) * Marcus Eugene Jones (1852–1934) * Liberty Hyde Bailey (1858–1954) *

Nathaniel Lord Britton Nathaniel Lord Britton (January 15, 1859 – June 25, 1934) was an American botanist and taxonomist who co-founded the New York Botanical Garden in the Bronx, New York. Early life Britton was born in New Dorp in Staten Island, New York to Jasp ...

(1859–1934) * Aven Nelson (1859–1952) *

Per Axel Rydberg Per Axel Rydberg (July 6, 1860 – July 25, 1931) was a Swedish-born, American botanist who was the first curator of the New York Botanical Garden Herbarium. Biography Per Axel Rydberg was born in Odh, Västergötland, Sweden and emigrated t ...

(1860–1931) *

Alfred Rehder Alfred Rehder (4 September 1863 in Waldenburg, Saxony – 25 July 1949 in Jamaica Plain, Massachusetts) was a German-American botanical taxonomist and dendrologist who worked at the Arnold Arboretum of Harvard University. He is generally reg ...

(1863–1949) *

Albert Spear Hitchcock Albert Spear Hitchcock (September 4, 1865 – December 16, 1935) was an American botanist and agrostologist. Hitchcock graduated from the Iowa Agricultural College with bachelor's degree in 1884 and M.S. in 1886. From 1892 to 1901 he was a pro ...

(1865–1935) *

Charles Piper Charles Vancouver Piper (16 June 1867 – 11 February 1926) was an American botanist and agriculturalist. Born in Victoria, British Columbia, Canada, he spent his youth in Seattle, Washington Territory and graduated from the University of Washi ...

(1867–1926) * Willis Lynn Jepson (1867–1946) *

John Kunkel Small John Kunkel Small (January 31, 1869 – January 20, 1938) was an American botanist. Born on January 31, 1869, in Harrisburg Pennsylvania, Kunkel studied botany at Franklin & Marshall College and Columbia University. He was the first Curator of ...

(1869–1938) * Mary Agnes Chase (1869–1963) *

Merritt Lyndon Fernald Merritt Lyndon Fernald (October 5, 1873 – September 22, 1950) was an American botanist. He was a respected scholar of the taxonomy and phytogeography of the vascular plant flora of temperate eastern North America. During his career, Fernald pub ...

(1873–1950) *

LeRoy Abrams LeRoy Abrams (1874–1956) was an American botanist and author. He was a Professor of Botany at Stanford University Stanford University, officially Leland Stanford Junior University, is a private research university in Stanford, Californ ...

(1874–1956) * Henry Allan Gleason (1882–1975) *

Paul Carpenter Standley Paul Carpenter Standley (March 21, 1884 – June 2, 1963) was an American botanist known for his work on neotropical plants. __TOC__ Standley was born on March 21, 1884 in Avalon, Missouri. He attended Drury College in Springfield, Missouri an ...

(1884–1963) * Edgar Theodore Wherry (1885–1982) * Earl Edward Scherff (1886–1966) *

Emma Lucy Braun E. Lucy Braun (April 19, 1889 – March 5, 1971) was a prominent botanist, ecologist, and expert on the forests of the eastern United States who was a professor of the University of Cincinnati. She was the first woman to be elected President o ...

(1889–1971) * Philip Alexander Munz (1892–1974) * Harold St. John (1892–1991) *

Eric Hultén Oskar Eric Gunnar Hultén (18 March 1894 – 1 February 1981) was a Swedish botanist, plant geographer and 20th century explorer of The Arctic. He was born in Halla in Södermanland. He took his licentiate exam 1931 at Stockholm University and ...

(1894–1981) *

Ivan Murray Johnston I. M. (Ivan Murray) Johnston (February 28, 1898–May 31, 1960), was a United States botanist. He studied at Pomona College in Claremont, California and at Harvard University. His plant collections are housed in the '' Rancho Santa Ana Botanic ...

(1898–1960) * Charles Leo Hitchcock (1902–1986) * Frederick Joseph Hermann (1906–1987) *

George Ledyard Stebbins George Ledyard Stebbins Jr. (January 6, 1906 – January 19, 2000) was an American botanist and geneticist who is widely regarded as one of the leading evolutionary biologists of the 20th century. Stebbins received his Ph.D. in botany from H ...

(1906–2000) * Elbert Luther Little, Jr. (1907–2004) *

Julian Alfred Steyermark Julian Alfred Steyermark (January 27, 1909 – October 15, 1988) was a Venezuelan American botanist. His focus was on New World vegetation, and he specialized in the family Rubiaceae. Life and work Julian Alfred Steyermark was born in St. Louis, ...

(1909–1988) * Lyman David Benson (1909–1993) * Reed Clark Rollins (1911–1998) *

Rupert Charles Barneby Rupert Charles Barneby (6 October 1911 – 5 December 2000) was a British-born self-taught botanist whose primary specialty was the Fabaceae (Leguminosae), the pea family, but he also worked on Menispermaceae and numerous other groups. He was em ...

(1911–2000) * Albert Ernest Radford (1918–2006) * Warren Herbert Wagner (1920–2000) * William Alfred Weber (b. 1918) *

Arthur Cronquist Arthur John Cronquist (March 19, 1919 – March 22, 1992) was an American biologist, botanist and a specialist on Compositae. He is considered one of the most influential botanists of the 20th century, largely due to his formulation of the Cr ...

(1919–1992) *

Ronald Leighton McGregor Ronald is a masculine given name derived from the Old Norse ''Rögnvaldr'', Hanks; Hardcastle; Hodges (2006) p. 234; Hanks; Hodges (2003) § Ronald. or possibly from Old English '' Regenweald''. In some cases ''Ronald'' is an Anglicised form of ...

(born 1919) *

Carlyle August Luer Carlyle August Luer (August 23, 1922 – November 9, 2019) was a botanist specializing in the Orchidaceae. His specialty interest was the Pleurothallidinae (Genus ''Pleurothallis'') and allied species. Born to Carl & Vera Luer, he was raised i ...

(born 1922) * Robert Kral (born 1926) *

Stanley Larson Welsh Stanley Larson Welsh (born 1928) is an American botanist. He has worked as professor of integrative biology at Brigham Young University for 44 years and was the founding curator of that university's herbarium, which is named after him. His fields a ...

(born 1928) * George William Argus (born 1929) * Edward Groesbeck Voss (1929–2012) * James Lauritz Reveal (1941–2015) *

Anton Alfred Reznicek Anton may refer to: People *Anton (given name), including a list of people with the given name *Anton (surname) Places *Anton Municipality, Bulgaria **Anton, Sofia Province, a village *Antón District, Panama **Antón, a town and capital of th ...

(born 1950) * Warren Lambert Wagner (born 1950) * Barbara Jean Ertter (born 1953) *

John Thomas Kartesz John is a common English name and surname: * John (given name) * John (surname) John may also refer to: New Testament Works * Gospel of John, a title often shortened to John * First Epistle of John, often shortened to 1 John * Second ...

Divisions

Some prominent botanists who have studied and published on U.S. flora

Further reading