''Trillium'' (trillium, wakerobin, toadshade, tri flower, birthroot, birthwort, and sometimes "wood lily") is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of about fifty

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

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), ...

in the family

Melanthiaceae Melanthiaceae, also called the bunchflower family, is a family (biology), family of flowering plant, flowering herbaceous perennial plants native to the Northern Hemisphere. Along with many other lilioid monocots, early authors considered member ...

. ''Trillium'' species are native to temperate regions of

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

and

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

, with the greatest diversity of species found in the southern

Appalachian Mountains The Appalachian Mountains, often called the Appalachians, are a mountain range in eastern to northeastern North America. The term "Appalachian" refers to several different regions associated with the mountain range, and its surrounding terrain ...

in 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 ...

Description

Plants of this genus are

perennial In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

herbs Herbs are a widely distributed and widespread group of plants, excluding vegetables, with savory or aromatic properties that are used for flavoring and garnish (food), garnishing food, for medicinal purposes, or for fragrances. Culinary use typi ...

growing from

rhizome In botany and dendrology, a rhizome ( ) is a modified subterranean plant stem that sends out roots and Shoot (botany), shoots from its Node (botany), nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from ...

s. There are three large leaf-like

bract In botany, a bract is a modified or specialized leaf, associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves in size, color, shape or texture. They also lo ...

s arranged in a whorl about a scape that rises directly from the rhizome. There are no true aboveground leaves but sometimes there are scale-like leaves on the underground rhizome. The bracts are

photosynthetic Photosynthesis ( ) is a Biological system, system of biological processes by which Photoautotrophism, photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical ener ...

and are sometimes called leaves. The

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

is a single flower with three green or reddish

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 Etymology The term ''sepalum'' ...

s and three

petal Petals are modified leaves that form an inner whorl surrounding the reproductive parts of flowers. They are often brightly coloured or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corol ...

s in shades of red, purple, pink, white, yellow, or green. At the center of the flower there are six

stamen 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 filament ...

s and three stigmas borne on a very short style, if any. The fruit is fleshy and capsule-like or berrylike. The seeds have large, oily

elaiosome Elaiosomes ( ''élaion'' "oil" + ''sóma'' "body") are fleshy structures that are attached to the seeds of many plant species. The elaiosome is rich in lipids and proteins, and may be variously shaped. Many plants have elaiosomes that attract ...

s. Occasionally individuals have four-fold symmetry, with four bracts (leaves), four sepals, and four petals in the blossom.. The

tetramerous Merosity (from the greek "méros," which means "having parts")) refers to the number of component parts in a distinct whorl of a plant structure. The term is most commonly used in the context of a flower where it refers to the number of sepals in a ...

condition has been described for several species of ''Trillium'' including ''T. chloropetalum'', ''T. erectum'', ''T. grandiflorum'', ''T. maculatum'', ''T. sessile'', and ''T. undulatum''.

Taxonomy

In 1753, Swedish botanist

Carl Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

established the genus ''Trillium'' by recognizing three species, ''Trillium cernuum'', ''Trillium erectum'', and ''Trillium sessile''. The

type specimen In biology, a type is a particular wikt:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally associated. In other words, a type is an example that serves to ancho ...

''Trillium cernuum'' described by Linnaeus was actually ''Trillium catesbaei'', an oversight that subsequently led to much confusion regarding the type species of this genus. Initially the ''Trillium'' genus was placed in the family

Liliaceae The lily family, Liliaceae, consists of about 15 genera and 610 species of flowering plants within the order Liliales. They are monocotyledonous, perennial, herbaceous, often bulbous geophytes. Plants in this family have evolved with a fai ...

. In the nineteenth and early twentieth centuries it was sometimes placed in a smaller family,

Trilliaceae Trilliaceae was a family of flowering plants first named in 1846; however, most taxonomists now consider the genera formerly assigned to it to belong to the family Liliaceae. The APG IV system, of 2016 (unchanged from the APG system, of 1998), d ...

. By 1981

had grown to about 280 genera and 4,000 species. As it became clearer that the very large version of Liliaceae was

polyphyletic A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies ...

, some botanists preferred to place ''Trillium'' and related genera into that separate family. Others defined a larger family,

, for a similar purpose, but included several other genera not historically recognized as close relatives of ''Trillium''. This latter approach was followed in 1998 by the

Angiosperm Phylogeny Group The Angiosperm Phylogeny Group (APG) is an informal international group of systematic botanists who collaborate to establish a consensus on the taxonomy of flowering plants (angiosperms) that reflects new knowledge about plant relationships disc ...

, which assigned the genus ''Trillium'', along with its close relative ''

Paris Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, largest city of France. With an estimated population of 2,048,472 residents in January 2025 in an area of more than , Paris is the List of ci ...

'', to the family Melanthiaceae. However, other taxonomists have since preferred to break up the heterogenous Melanthiaceae into several smaller monophyletic families, each with more coherent morphological features, returning ''Trillium'' to a resurrected Trilliaceae. In 1850, German botanist

Carl Sigismund Kunth Carl Sigismund Kunth (18 June 1788 – 22 March 1850) was a German botanist. He was also known as Karl Sigismund Kunth or anglicized as Charles Sigismund Kunth. He was one of the early systematic botanists who focused on studying the plants of th ...

segregated ''Trillium govanianum'' into genus ''Trillidium''. Some authorities consider ''Trillidium'' to be a synonym for ''Trillium'' , while others recognize the taxon ''Trillidium govanianum'' based on morphological differences (with other ''Trillium'' species) and molecular evidence. Still others support the segregation of ''Trillium undulatum'' into genus ''Trillidium'' alongside ''Trillidium govanianum''.

Subdivisions

All names used in this section are taken from the

International Plant Names Index The International Plant Names Index (IPNI) describes itself as "a database of the names and associated basic bibliographical details of seed plants, ferns and lycophytes." Coverage of plant names is best at the rank of species and genus. It inclu ...

. ,

Plants of the World Online Plants of the World Online (POWO) is an online taxonomic database published by the Royal Botanic Gardens, Kew. History Following the Convention on Biological Diversity, the Royal Botanic Gardens in Kew launched Plants of the World Online i ...

(POWO) accepts 49 species and 5 named hybrids, all of which are listed below. The geographical locations are taken from POWO and the

Flora of North America The ''Flora of North America North of Mexico'' (usually referred to as ''FNA'') is a multivolume work describing the native plants and naturalized plants of North America, including the United States, Canada, St. Pierre and Miquelon, and Greenla ...

, except where noted. The ''Trillium'' genus has traditionally been divided into two

subgenera In biology, a subgenus ( subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the ge ...

, ''Trillium'' subgenus ''Trillium'' and ''Trillium'' subgenus ''Phyllantherum'', based on whether the flower is pedicellate or sessile. At the time, the former subgenus was considered to be the more primitive group. Based on

molecular systematics Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

, ''Trillium'' subgen. ''Phyllantherum'' has been shown to be a

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

group, but its segregation renders the remaining ''Trillium'' subgen. ''Trillium''

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

. ''Trillium'' subgenus ''Phyllantherum'' was named by

Constantine Samuel Rafinesque Constantine Samuel Rafinesque-Schmaltz (; 22 October 178318 September 1840) was a French early 19th-century polymath born near Constantinople in the Ottoman Empire and self-educated in France. He traveled as a young man in the United States, ult ...

in 1820, but since he did not provide a description, the name was declared invalid in 2014. At that time, the correct name was thought to be ''Trillium'' subgen. ''Sessilium'', which was described by Rafinesque in 1830. However, that name was later found to be incorrect as well. , the correct name of the subgenus is ''Trillium'' subgen. ''Sessilia'' Its

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

is ''Trillium sessile'' In 1819, Rafinesque described and named the genus ''Delostylis'', and then placed ''Trillium stylosum'' (now a synonym for ''Trillium catesbaei'' ) into the new genus. Reversing himself a decade later, Rafinesque instead placed ''Trillium stylosum'' into a new subgenus ''Delostylium'' in 1830. Presumably Rafinesque had intended the subgeneric name to replace the earlier generic name, and so the correct name of the former is ''Trillium'' subgen. ''Delostylis'' . Its type species is ''Trillium catesbaei''. Historically, the subgenus has been known as the Catesbaei group. The word ''Delostylis'' means "with a small but conspicuous style". Based on

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

and molecular evidence, a few taxa in genus ''Trillium'' have been segregated into other genera: * ''Trillium rivale'', first described in 1885, was segregated into genus ''Pseudotrillium'' in 2002. The name ''Pseudotrillium rivale'' is widely recognized. * ''Trillium govanianum'', first described in 1839, was segregated into genus ''Trillidium'' in 1850. However, the name ''Trillidium govanianum'' is not widely recognized. * ''Trillium undulatum'', first described in 1801, was segregated into genus ''Trillidium'' in 2018, but the name ''Trillidium undulatum'' is controversial and not widely recognized.

Phylogenetic analysis In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical data ...

places ''Trillidium govanianum'' and ''Trillidium undulatum'' together in a clade with high support. However, since ''Trillium'' and ''Trillidium'' are both individually and collectively monophyletic, it is a matter of choice whether or not to recognize genus ''Trillidium''. Excluding the segregate taxa listed above, the remaining taxa separate into four clades with the following names: # ''Trillium'' subgen. ''Trillium'' # ''Trillium'' subgen. ''Callipetalon'' # ''Trillium'' subgen. ''Delostylis'' s Delostylium# ''Trillium'' subgen. ''Sessilia'' s Sessilium Traditionally, ''Trillium'' subgen. ''Trillium'' has included all pedicellate-flowered species (which is a

group), but in 2022, the subgenus was circumscribed as a

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

of fourteen (14) species. Its type species is ''Trillium erectum'' Historically, the subgenus has been known as the Erectum group. ''Trillium'' subgen. ''Callipetalon'' was described by Jayne A. Lampley and Edward E. Schilling in 2022. The word ''Callipetalon'' means "beautiful petal", a reference to "the famously beautiful flowers" of its type species, ''Trillium grandiflorum'' Historically, the subgenus has been known as the Grandiflorum group. This leads to a four-part concept of ''Trillium'' that sharply contrasts with the traditional pedicellate vs. sessile dichotomy outlined previously.

Subgenus ''Trillium''

''Trillium'' subgen. ''Trillium'', the Erectum group, is a group of pedicellate-flowered trilliums that includes ''

Trillium erectum ''Trillium erectum'', the red trillium, also known as wake robin, purple trillium, bethroot, or stinking benjamin, is a species of flowering plant in the family Melanthiaceae. The plant takes its common name "wake robin" by analogy with the Euro ...

''. The subgenus was circumscribed as a

of fourteen (14) species in 2022. Species in this subgenus have pedicellate flowers (on a stalk) with three distinct stigmas (no

style Style, or styles may refer to: Film and television * ''Style'' (2001 film), a Hindi film starring Sharman Joshi, Riya Sen, Sahil Khan and Shilpi Mudgal * ''Style'' (2002 film), a Tamil drama film * ''Style'' (2004 film), a Burmese film * '' ...

) and solid green leaves (not mottled). They are distributed across North America and Asia. Hybrids are common within this subgenus (the only group of pedicellate-flowered trilliums with natural hybrids). * '' Trillium apetalon'' – Japan, Kuril Islands, E Russia (Sakhalin) * '' Trillium camschatcense'' – NE China (Jilin), Japan, Korea, Kuril Islands, E Russia (Primorsky Krai, Khabarovsk Krai, Kamchatka Peninsula, Sakhalin) * ''

Trillium cernuum ''Trillium cernuum'' is a species of flowering plant in the bunchflower family Melanthiaceae. The specific epithet ''cernuum'' means "drooping, curving forwards, facing downwards", a distinctive habit of its flower. It is commonly called noddi ...

'' – Manitoba, New Brunswick, Newfoundland, Nova Scotia, Ontario, Prince Edward Island, Quebec, Saskatchewan; Connecticut, Delaware, Illinois, Indiana, Iowa, Maine, Maryland, Massachusetts, Michigan, Minnesota, New Hampshire, New Jersey, New York, North Dakota, Ohio, Pennsylvania, Rhode Island, South Dakota, Vermont, Virginia, West Virginia, Wisconsin; Saint Pierre and Miquelon * '' Trillium channellii'' – Japan (E Hokkaido) * ''

'' – New Brunswick, Nova Scotia, Ontario, Quebec; Connecticut, Delaware, Georgia, Illinois, Indiana, Kentucky, Maine, Maryland, Massachusetts, Michigan, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Vermont, Virginia, West Virginia * '' Trillium flexipes'' – Ontario; Alabama, Arkansas, Delaware, Illinois, Indiana, Iowa, Kentucky, Maryland, Michigan, Minnesota, Missouri, New York, Ohio, Pennsylvania, South Dakota, Tennessee, Virginia, West Virginia, Wisconsin * ''Trillium'' × ''hagae'' (''Trillium camschatcense'' × ''Trillium tschonoskii'') – Japan, E Russia (S Sakhalin) * '' Trillium hibbersonii'' – British Columbia * ''Trillium'' × ''komarovii'' (''Trillium camschatcense'' × unknown) – Japan, E Russia (Primorsky Krai) * ''Trillium'' × ''miyabeanum'' (''Trillium apetalon'' × ''Trillium tschonoskii'') – Japan * '' Trillium rugelii'' – Alabama, Georgia, North Carolina, South Carolina, Tennessee * '' Trillium simile'' – Georgia, North Carolina, Tennessee * '' Trillium smallii'' – Japan, E Russia (S Sakhalin) * '' Trillium sulcatum'' – Alabama, Georgia, Kentucky, North Carolina, Tennessee, Virginia, West Virginia * '' Trillium taiwanense'' – E Taiwan * '' Trillium tschonoskii'' – Bhutan, China (Anhui, Fujian, Gansu, Hubei, Shaanxi, Sichuan, Tibet Autonomous Region, Yunnan, Zhejiang), NE India (Sikkim), Japan, Korea, Kuril Islands, Myanmar, Russia (Sakhalin), Taiwan * '' Trillium vaseyi'' – Alabama, Georgia, North Carolina, South Carolina, Tennessee * ''Trillium'' × ''yezoense'' (''Trillium apetalon'' × ''Trillium camschatcense'') – Japan

Subgenus ''Callipetalon''

''Trillium'' subgen. ''Callipetalon'', the Grandiflorum group, is a group of pedicellate-flowered trilliums that includes ''

Trillium grandiflorum ''Trillium grandiflorum'', the white trillium, large-flowered trillium, great white trillium, white wake-robin or , is a species of flowering plant in the family (biology), family Melanthiaceae. A monocotyledonous, herbaceous plant, herbaceou ...

''. The subgenus was circumscribed as a

of three (3) species in 2022. Species in the subgenus have pedicellate flowers (on a stalk) and solid green leaves (except ''T. ovatum'' on the west coast of California, which occasionally has mottled leaves). The stigmas are fused together at their bases (basally connate) but lack a definite

. They are distributed across North America (but not Asia). Flowers were and still are consumed and used by

indigenous peoples There is no generally accepted definition of Indigenous peoples, although in the 21st century the focus has been on self-identification, cultural difference from other groups in a state, a special relationship with their traditional territ ...

in various regions of North America. * ''

Trillium crassifolium ''Trillium crassifolium'', the Wenatchee Mountains trillium, is a species of flowering plant in the bunchflower family (biology), family Melanthiaceae. It was previously thought to be endemic to the Wenatchee Mountains in Washington (state), Wash ...

'' – Washington * ''

'' – Nova Scotia, Ontario, Quebec; Alabama, Connecticut, Delaware, District of Columbia, Georgia, Illinois, Indiana, Iowa, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, South Carolina, Tennessee, Vermont, Virginia, West Virginia, Wisconsin * '' Trillium nivale'' – Illinois, Indiana, Iowa, Kentucky, Maryland, Michigan, Minnesota, Missouri, Nebraska, Ohio, Pennsylvania, South Dakota, West Virginia, Wisconsin * '' Trillium ovatum'' – Alberta, British Columbia; California, Colorado, Idaho, Montana, Oregon, Washington, Wyoming * '' Trillium scouleri'' – Alberta, British Columbia; Colorado, Idaho, Montana, Washington, Wyoming

Subgenus ''Delostylis''

''Trillium'' subgen. ''Delostylis'', the Catesbaei group, is a group of pedicellate-flowered trilliums that includes '' Trillium catesbaei''. The subgenus was circumscribed as a

of seven (7) species in 2022. Species in this subgenus have pedicellate flowers (except for one variety of ''T. pusillum'') with a definite

and solid green leaves (not mottled). Distribution is restricted to the southeastern and south central United States. * '' Trillium catesbaei'' – Alabama, Georgia, North Carolina, South Carolina, Tennessee * '' Trillium georgianum'' – Georgia * '' Trillium persistens'' – Georgia, South Carolina * '' Trillium pusillum'' – Alabama, Arkansas, Kentucky, Maryland, Mississippi, Missouri, North Carolina, Oklahoma, South Carolina, Tennessee, Virginia, West Virginia * '' Trillium texanum'' – Arkansas, Louisiana, Texas

Subgenus ''Sessilia''

''Trillium'' subgen. ''Sessilia'', the sessile-flowered trilliums, is a group of species that includes '' Trillium sessile''. The subgenus was circumscribed as a

of twenty-six (26) species in 2022. Species in this subgenus have sessile flowers (no flower stalk), erect petals (except in ''T. stamineum''), and mottled leaves (except in ''T. petiolatum'' and occasionally in plants of other sessile-flowered species). * '' Trillium albidum'' – California, Oregon, Washington * '' Trillium angustipetalum'' – California * '' Trillium chloropetalum'' – California * '' Trillium cuneatum'' – Alabama, Georgia, Kentucky, Mississippi, North Carolina, South Carolina, Tennessee * '' Trillium decipiens'' – Alabama, Florida, Georgia * '' Trillium decumbens'' – Alabama, Georgia, Tennessee * '' Trillium delicatum'' – Georgia * '' Trillium discolor'' – Georgia, North Carolina, South Carolina * '' Trillium foetidissimum'' – Louisiana, Mississippi * '' Trillium gracile'' – Louisiana, Texas * '' Trillium kurabayashii'' – California, Oregon * '' Trillium lancifolium'' – Alabama, Florida, Georgia, South Carolina, Tennessee * '' Trillium ludovicianum'' – Louisiana, Mississippi, Texas * '' Trillium luteum'' – District of Columbia, Georgia, Kentucky, North Carolina, Tennessee * '' Trillium maculatum'' – Alabama, Florida, Georgia, South Carolina * '' Trillium oostingii'' – South Carolina * '' Trillium petiolatum'' – Idaho, Oregon, Washington * '' Trillium recurvatum'' – Alabama, Arkansas, Illinois, Indiana, Iowa, Kentucky, Louisiana, Michigan, Mississippi, Missouri, Ohio, Tennessee, Texas, Wisconsin * '' Trillium reliquum'' – Georgia, South Carolina * '' Trillium sessile'' – Alabama, Arkansas, District of Columbia, Illinois, Indiana, Kansas, Kentucky, Maryland, Michigan, Missouri, New York, North Carolina, Ohio, Oklahoma, Pennsylvania, Tennessee, Virginia, West Virginia * '' Trillium stamineum'' – Alabama, Mississippi, Tennessee * '' Trillium tennesseense'' – Tennessee * '' Trillium underwoodii'' – Alabama, Florida, Georgia * '' Trillium viride'' – Illinois, Missouri * '' Trillium viridescens'' – Arkansas, Kansas, Missouri, Oklahoma, Texas

Ungrouped taxa

The following pair of taxa do not fit into any of the above groups since they are markedly different from other ''Trillium'' species. There is evidence to support the segregation of these species into a separate genus (''Trillidium'') but the proposal is controversial. * '' Trillium govanianum'' – NE Afghanistan, Bhutan, China (Tibet Autonomous Region, Yunnan), N + NE India (Himachal Pradesh, Jammu and Kashmir, Sikkim, Uttarakhand), Nepal, N Pakistan * '' Trillium undulatum'' – New Brunswick, Nova Scotia, Ontario, Prince Edward Island, Quebec; Connecticut, Georgia, Kentucky, Maine, Maryland, Massachusetts, Michigan, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Vermont, Virginia, West Virginia

Other taxa

does not accept these taxa: * ''Trillium parviflorum'' is an accepted name by some authorities while others regard this name as a synonym of ''T. albidum'' subsp. ''parviflorum'' . The following taxa are of historical interest: * ''Trillium rivale'' has been segregated to a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus as '' Pseudotrillium rivale'' . * ''Trillium'' × ''crockerianum'' was originally described as a hybrid with parents ''Trillium ovatum'' and ''Trillium rivale'', but since the latter is now a member of genus '' Pseudotrillium'', the hybrid has become an undescribed intergeneric hybrid, and therefore its taxonomic placement is uncertain.

Distribution

''Trillium'' species are native to North America and Asia.

North America

More than three dozen ''Trillium'' species are found in North America, most of which are native to eastern North America. Just six species are native to western North America: ''T. albidum'', ''T. angustipetalum'', ''T. chloropetalum'', ''T. kurabayashii'', ''T. ovatum'', and ''T. petiolatum''. Of these, only ''T. ovatum'' is pedicellate-flowered.

Canada

''Trillium'' species are found across

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

, from Newfoundland to southern British Columbia. The greatest diversity of species are found in Ontario, Quebec, and Nova Scotia. *

Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...

: ''T. ovatum'', ''T. scouleri'' *

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

: ''T. hibbersonii'', ''T. ovatum'', ''T. scouleri'' *

Manitoba Manitoba is a Provinces and territories of Canada, province of Canada at the Centre of Canada, longitudinal centre of the country. It is Canada's Population of Canada by province and territory, fifth-most populous province, with a population ...

: ''T. cernuum'' *

New Brunswick New Brunswick is a Provinces and Territories of Canada, province of Canada, bordering Quebec to the north, Nova Scotia to the east, the Gulf of Saint Lawrence to the northeast, the Bay of Fundy to the southeast, and the U.S. state of Maine to ...

: ''T. cernuum'', ''T. erectum'', ''T. undulatum'' *

Newfoundland Newfoundland and Labrador is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region of Labrador, having a total size of . As of 2025 the population ...

: ''T. cernuum'' *

Northwest Territories The Northwest Territories is a federal Provinces and territories of Canada, territory of Canada. At a land area of approximately and a 2021 census population of 41,070, it is the second-largest and the most populous of Provinces and territorie ...

: none *

Nova Scotia Nova Scotia is a Provinces and territories of Canada, province of Canada, located on its east coast. It is one of the three Maritime Canada, Maritime provinces and Population of Canada by province and territory, most populous province in Atlan ...

: ''T. cernuum'', ''T. erectum'', ''T. grandiflorum'', ''T. undulatum'' *

Nunavut Nunavut is the largest and northernmost Provinces and territories of Canada#Territories, territory of Canada. It was separated officially from the Northwest Territories on April 1, 1999, via the ''Nunavut Act'' and the Nunavut Land Claims Agr ...

: none *

Ontario Ontario is the southernmost Provinces and territories of Canada, province of Canada. Located in Central Canada, Ontario is the Population of Canada by province and territory, country's most populous province. As of the 2021 Canadian census, it ...

: ''T. cernuum'', ''T. erectum'', ''T. flexipes'', ''T. grandiflorum'', ''T. undulatum'' *

Prince Edward Island Prince Edward Island is an island Provinces and territories of Canada, province of Canada. While it is the smallest province by land area and population, it is the most densely populated. The island has several nicknames: "Garden of the Gulf", ...

: ''T. cernuum'', ''T. undulatum'' *

Quebec Quebec is Canada's List of Canadian provinces and territories by area, largest province by area. Located in Central Canada, the province shares borders with the provinces of Ontario to the west, Newfoundland and Labrador to the northeast, ...

: ''T. cernuum'', ''T. erectum'', ''T. grandiflorum'', ''T. undulatum'' *

Saskatchewan Saskatchewan is a Provinces and territories of Canada, province in Western Canada. It is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and to the south by the ...

: ''T. cernuum'' *

Yukon Yukon () is a Provinces and territories of Canada, territory of Canada, bordering British Columbia to the south, the Northwest Territories to the east, the Beaufort Sea to the north, and the U.S. state of Alaska to the west. It is Canada’s we ...

: none

United States

Except for the desert regions of the

southwestern United States The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural list of regions of the United States, region of the United States that includes Arizona and New Mexico, along with adjacen ...

, ''Trillium'' species are found throughout the contiguous U.S. states. In the

western United States The Western United States (also called the American West, the Western States, the Far West, the Western territories, and the West) is List of regions of the United States, census regions United States Census Bureau. As American settlement i ...

, species are found from Washington to central California, east to the

Rocky Mountains The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in great-circle distance, straight-line distance from the northernmost part of Western Can ...

. In the

eastern United States The Eastern United States, often abbreviated as simply the East, is a macroregion of the United States located to the east of the Mississippi River. It includes 17–26 states and Washington, D.C., the national capital. As of 2011, the Eastern ...

, species range from Maine to northern Florida, west to the

Mississippi River The Mississippi River is the main stem, primary river of the largest drainage basin in the United States. It is the second-longest river in the United States, behind only the Missouri River, Missouri. From its traditional source of Lake Ita ...

valley. ''Trillium'' species are especially diverse in the

southeastern United States The Southeastern United States, also known as the American Southeast or simply the Southeast, is a geographical List of regions in the United States, region of the United States located in the eastern portion of the Southern United States and t ...

, in Georgia, Tennessee, Alabama, North Carolina, and South Carolina. The state of Georgia is home to 21 species of trillium. *

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 ...

: ''T. catesbaei'', ''T. cuneatum'', ''T. decipiens'', ''T. decumbens'', ''T. flexipes'', ''T. grandiflorum'', ''T. lancifolium'', ''T. luteum'', ''T. maculatum'', ''T. pusillum'', ''T. recurvatum'', ''T. reliquum'', ''T. rugelii'', ''T. sessile'', ''T. stamineum'', ''T. sulcatum'', ''T. underwoodii'', ''T. vaseyi'' *

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

: none *

Arizona Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the nort ...

: none *

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 ...

: ''T. flexipes'', ''T. pusillum'', ''T. recurvatum'', ''T. sessile'', ''T. texanum'', ''T. viridescens'' *

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

: ''T. albidum'', ''T. angustipetalum'', ''T. chloropetalum'', ''T. kurabayashii'', ''T. ovatum'' *

Colorado Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...

: ''T. ovatum'', ''T. scouleri'' *

Connecticut Connecticut ( ) is a U.S. state, state in the New England region of the Northeastern United States. It borders Rhode Island to the east, Massachusetts to the north, New York (state), New York to the west, and Long Island Sound to the south. ...

: ''T. cernuum'', ''T. erectum'', ''T. grandiflorum'', ''T. undulatum'' *

Delaware Delaware ( ) is a U.S. state, state in the Mid-Atlantic (United States), Mid-Atlantic and South Atlantic states, South Atlantic regions of the United States. It borders Maryland to its south and west, Pennsylvania to its north, New Jersey ...

: ''T. cernuum'', ''T. erectum'', ''T. flexipes'', ''T. grandiflorum'' *

District of Columbia Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and Federal district of the United States, federal district of the United States. The city is on the Potomac River, across from ...

: ''T. grandiflorum'', ''T. luteum'', ''T. sessile'' *

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 ...

: ''T. decipiens'', ''T. lancifolium'', ''T. maculatum'', ''T. underwoodii'' *

Georgia Georgia most commonly refers to: * Georgia (country), a country in the South Caucasus * Georgia (U.S. state), a state in the southeastern United States Georgia may also refer to: People and fictional characters * Georgia (name), a list of pe ...

: ''T. catesbaei'', ''T. cuneatum'', ''T. decipiens'', ''T. decumbens'', ''T. delicatum'', ''T. discolor'', ''T. erectum'', ''T. georgianum'', ''T. grandiflorum'', ''T. lancifolium'', ''T. luteum'', ''T. maculatum'', ''T. persistens'', ''T. reliquum'', ''T. rugelii'', ''T. simile'', ''T. sulcatum'', ''T. underwoodii'', ''T. undulatum'', ''T. vaseyi'' *

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

: none *

Idaho Idaho ( ) is a landlocked U.S. state, state in the Pacific Northwest and Mountain states, Mountain West subregions of the Western United States. It borders Montana and Wyoming to the east, Nevada and Utah to the south, and Washington (state), ...

: ''T. ovatum'', ''T. petiolatum'', ''T. scouleri'' *

Illinois Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its ...

: ''T. cernuum'', ''T. erectum'', ''T. flexipes'', ''T. grandiflorum'', ''T. nivale'', ''T. recurvatum'', ''T. sessile'', ''T. viride'' *

Indiana Indiana ( ) is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Lake Michigan to the northwest, Michigan to the north and northeast, Ohio to the east, the Ohio River and Kentucky to the s ...

: ''T. cernuum'', ''T. erectum'', ''T. flexipes'', ''T. grandiflorum'', ''T. nivale'', ''T. recurvatum'', ''T. sessile'' *

Iowa Iowa ( ) is a U.S. state, state in the upper Midwestern United States, Midwestern region of the United States. It borders the Mississippi River to the east and the Missouri River and Big Sioux River to the west; Wisconsin to the northeast, Ill ...

: ''T. cernuum'', ''T. flexipes'', ''T. grandiflorum'', ''T. nivale'', ''T. recurvatum'' *

Kansas Kansas ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the west. Kansas is named a ...

: ''T. sessile'', ''T. viridescens'' *

Kentucky Kentucky (, ), officially the Commonwealth of Kentucky, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Illinois, Indiana, and Ohio to the north, West Virginia to the ...

: ''T. cuneatum'', ''T. erectum'', ''T. flexipes'', ''T. grandiflorum'', ''T. luteum'', ''T. nivale'', ''T. pusillum'', ''T. recurvatum'', ''T. sessile'', ''T. sulcatum'', ''T. undulatum'' *

Louisiana Louisiana ( ; ; ) is a state in the Deep South and South Central regions of the United States. It borders Texas to the west, Arkansas to the north, and Mississippi to the east. Of the 50 U.S. states, it ranks 31st in area and 25 ...

: ''T. foetidissimum'', ''T. gracile'', ''T. ludovicianum'', ''T. recurvatum'', ''T. texanum'' *

Maine Maine ( ) is a U.S. state, state in the New England region of the United States, and the northeasternmost state in the Contiguous United States. It borders New Hampshire to the west, the Gulf of Maine to the southeast, and the Provinces and ...

: ''T. cernuum'', ''T. erectum'', ''T. grandiflorum'', ''T. undulatum'' *

Maryland Maryland ( ) is a U.S. state, state in the Mid-Atlantic (United States), Mid-Atlantic region of the United States. It borders the states of Virginia to its south, West Virginia to its west, Pennsylvania to its north, and Delaware to its east ...

: ''T. cernuum'', ''T. erectum'', ''T. flexipes'', ''T. grandiflorum'', ''T. nivale'', ''T. pusillum'', ''T. sessile'', ''T. undulatum'' *

Massachusetts Massachusetts ( ; ), officially the Commonwealth of Massachusetts, is a U.S. state, state in the New England region of the Northeastern United States. It borders the Atlantic Ocean and the Gulf of Maine to its east, Connecticut and Rhode ...

: ''T. cernuum'', ''T. erectum'', ''T. grandiflorum'', ''T. undulatum'' *

Michigan Michigan ( ) is a peninsular U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest, Upper Midwestern United States. It shares water and land boundaries with Minnesota to the northwest, Wisconsin to the west, ...

: ''T. cernuum'', ''T. erectum'', ''T. flexipes'', ''T. grandiflorum'', ''T. nivale'', ''T. recurvatum'', ''T. sessile'', ''T. undulatum'' *

Minnesota Minnesota ( ) is a U.S. state, state in the Upper Midwestern region of the United States. It is bordered by the Canadian provinces of Manitoba and Ontario to the north and east and by the U.S. states of Wisconsin to the east, Iowa to the so ...

: ''T. cernuum'', ''T. flexipes'', ''T. grandiflorum'', ''T. nivale'' *

Mississippi Mississippi ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South regions of the United States. It borders Tennessee to the north, Alabama to the east, the Gulf of Mexico to the south, Louisiana to the s ...

: ''T. cuneatum'', ''T. foetidissimum'', ''T. ludovicianum'', ''T. pusillum'', ''T. recurvatum'', ''T. stamineum'' *

Missouri Missouri (''see #Etymology and pronunciation, pronunciation'') is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. Ranking List of U.S. states and territories by area, 21st in land area, it border ...

: ''T. flexipes'', ''T. nivale'', ''T. pusillum'', ''T. recurvatum'', ''T. sessile'', ''T. viride'', ''T. viridescens'' *

Montana Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, an ...

: ''T. ovatum'', ''T. scouleri'' *

Nebraska Nebraska ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Ka ...

: ''T. nivale'' *

Nevada Nevada ( ; ) is a landlocked state in the Western United States. It borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the seventh-most extensive, th ...

: none *

New Hampshire New Hampshire ( ) is a U.S. state, state in the New England region of the Northeastern United States. It borders Massachusetts to the south, Vermont to the west, Maine and the Gulf of Maine to the east, and the Canadian province of Quebec t ...

: ''T. cernuum'', ''T. erectum'', ''T. grandiflorum'', ''T. undulatum'' *

New Jersey New Jersey is a U.S. state, state located in both the Mid-Atlantic States, Mid-Atlantic and Northeastern United States, Northeastern regions of the United States. Located at the geographic hub of the urban area, heavily urbanized Northeas ...

: ''T. cernuum'', ''T. erectum'', ''T. grandiflorum'', ''T. undulatum'' *

New Mexico New Mexico is a state in the Southwestern United States, Southwestern region of the United States. It is one of the Mountain States of the southern Rocky Mountains, sharing the Four Corners region with Utah, Colorado, and Arizona. It also ...

: none *

New York New York most commonly refers to: * New York (state), a state in the northeastern United States * New York City, the most populous city in the United States, located in the state of New York New York may also refer to: Places United Kingdom * ...

: ''T. cernuum'', ''T. erectum'', ''T. flexipes'', ''T. grandiflorum'', ''T. sessile'', ''T. undulatum'' *

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 ...

: ''T. catesbaei'', ''T. cuneatum'', ''T. discolor'', ''T. erectum'', ''T. grandiflorum'', ''T. luteum'', ''T. pusillum'', ''T. rugelii'', ''T. sessile'', ''T. simile'', ''T. sulcatum'', ''T. undulatum'', ''T. vaseyi'' *

North Dakota North Dakota ( ) is a U.S. state in the Upper Midwest, named after the indigenous Dakota people, Dakota and Sioux peoples. It is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north and by the U.S. states of Minneso ...

: ''T. cernuum'' *

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 ...

: ''T. cernuum'', ''T. erectum'', ''T. flexipes'', ''T. grandiflorum'', ''T. nivale'', ''T. recurvatum'', ''T. sessile'', ''T. undulatum'' *

Oklahoma Oklahoma ( ; Choctaw language, Choctaw: , ) is a landlocked U.S. state, state in the South Central United States, South Central region of the United States. It borders Texas to the south and west, Kansas to the north, Missouri to the northea ...

: ''T. pusillum'', ''T. sessile'', ''T. viridescens'' *

Oregon Oregon ( , ) is a U.S. state, state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington (state), Washington, while t ...

: ''T. albidum'', ''T. kurabayashii'', ''T. ovatum'', ''T. petiolatum'' *

Pennsylvania Pennsylvania, officially the Commonwealth of Pennsylvania, is a U.S. state, state spanning the Mid-Atlantic (United States), Mid-Atlantic, Northeastern United States, Northeastern, Appalachian, and Great Lakes region, Great Lakes regions o ...

: ''T. cernuum'', ''T. erectum'', ''T. flexipes'', ''T. grandiflorum'', ''T. nivale'', ''T. sessile'', ''T. undulatum'' *

Rhode Island Rhode Island ( ) is a state in the New England region of the Northeastern United States. It borders Connecticut to its west; Massachusetts to its north and east; and the Atlantic Ocean to its south via Rhode Island Sound and Block Is ...

: ''T. cernuum'', ''T. erectum'', ''T. undulatum'' *

South Carolina South Carolina ( ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders North Carolina to the north and northeast, the Atlantic Ocean to the southeast, and Georgia (U.S. state), Georg ...

: ''T. catesbaei'', ''T. cuneatum'', ''T. discolor'', ''T. erectum'', ''T. grandiflorum'', ''T. lancifolium'', ''T. maculatum'', ''T. oostingii'', ''T. persistens'', ''T. pusillum'', ''T. reliquum'', ''T. rugelii'', ''T. undulatum'', ''T. vaseyi'' *

South Dakota South Dakota (; Sioux language, Sioux: , ) is a U.S. state, state in the West North Central states, North Central region of the United States. It is also part of the Great Plains. South Dakota is named after the Dakota people, Dakota Sioux ...

: ''T. cernuum'', ''T. flexipes'', ''T. nivale'' *

Tennessee Tennessee (, ), officially the State of Tennessee, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Kentucky to the north, Virginia to the northeast, North Carolina t ...

: ''T. catesbaei'', ''T. cuneatum'', ''T. decumbens'', ''T. erectum'', ''T. flexipes'', ''T. grandiflorum'', ''T. lancifolium'', ''T. luteum'', ''T. pusillum'', ''T. recurvatum'', ''T. rugelii'', ''T. sessile'', ''T. simile'', ''T. stamineum'', ''T. sulcatum'', ''T. tennesseense'', ''T. undulatum'', ''T. vaseyi'' *

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

: ''T. gracile'', ''T. ludovicianum'', ''T. recurvatum'', ''T. texanum'', ''T. viridescens'' *

Utah Utah is a landlocked state in the Mountain states, Mountain West subregion of the Western United States. It is one of the Four Corners states, sharing a border with Arizona, Colorado, and New Mexico. It also borders Wyoming to the northea ...

: none *

Vermont Vermont () is a U.S. state, state in the New England region of the Northeastern United States. It borders Massachusetts to the south, New Hampshire to the east, New York (state), New York to the west, and the Provinces and territories of Ca ...

: ''T. cernuum'', ''T. erectum'', ''T. grandiflorum'', ''T. undulatum'' *

Virginia Virginia, officially the Commonwealth of Virginia, is a U.S. state, state in the Southeastern United States, Southeastern and Mid-Atlantic (United States), Mid-Atlantic regions of the United States between the East Coast of the United States ...

: ''T. cernuum'', ''T. erectum'', ''T. flexipes'', ''T. grandiflorum'', ''T. pusillum'', ''T. sessile'', ''T. sulcatum'', ''T. undulatum'' * Washington: ''T. albidum'', ''T. ovatum'', ''T. petiolatum'', ''T. scouleri'' *

West Virginia West Virginia is a mountainous U.S. state, state in the Southern United States, Southern and Mid-Atlantic (United States), Mid-Atlantic regions of the United States.The United States Census Bureau, Census Bureau and the Association of American ...

: ''T. cernuum'', ''T. erectum'', ''T. flexipes'', ''T. grandiflorum'', ''T. nivale'', ''T. pusillum'', ''T. sessile'', ''T. sulcatum'', ''T. undulatum'' *

Wisconsin Wisconsin ( ) is a U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest of the United States. It borders Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michig ...

: ''T. cernuum'', ''T. flexipes'', ''T. grandiflorum'', ''T. nivale'', ''T. recurvatum'' *

Wyoming Wyoming ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States, Western United States. It borders Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho t ...

: ''T. ovatum'', ''T. scouleri''

Other

Saint Pierre and Miquelon Saint Pierre and Miquelon ( ), officially the Territorial Collectivity of Saint Pierre and Miquelon (), is a self-governing territorial overseas collectivity of France in the northwestern Atlantic Ocean, located near the Canada, Canadian prov ...

: ''T. cernuum''

Asia

In Asia, the range of ''Trillium'' species extends from the

Himalayas The Himalayas, or Himalaya ( ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the Earth's highest peaks, including the highest, Mount Everest. More than list of h ...

across China, Korea, Japan, and eastern Russia to the Kuril Islands. The greatest diversity of ''Trillium'' species is found on the islands of Japan and Sakhalin. *

Afghanistan Afghanistan, officially the Islamic Emirate of Afghanistan, is a landlocked country located at the crossroads of Central Asia and South Asia. It is bordered by Pakistan to the Durand Line, east and south, Iran to the Afghanistan–Iran borde ...

: ''T. govanianum'' *

Bhutan Bhutan, officially the Kingdom of Bhutan, is a landlocked country in South Asia, in the Eastern Himalayas between China to the north and northwest and India to the south and southeast. With a population of over 727,145 and a territory of , ...

: ''T. govanianum'', ''T. tschonoskii'' *

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

: ''T. camschatcense'' (

Jilin ) , image_skyline = Changbaishan Tianchi from western rim.jpg , image_alt = , image_caption = View of Heaven Lake , image_map = Jilin in China (+all claims hatched).svg , mapsize = 275px , map_al ...

), ''T. govanianum'' (

Tibet Autonomous Region The Tibet Autonomous Region (TAR), often shortened to Tibet in English or Xizang in Pinyin, Hanyu Pinyin, is an Autonomous regions of China, autonomous region of the China, People's Republic of China. It was established in 1965 to replace the ...

Yunnan Yunnan; is an inland Provinces of China, province in Southwestern China. The province spans approximately and has a population of 47.2 million (as of 2020). The capital of the province is Kunming. The province borders the Chinese provinces ...

), ''T. taiwanense'' (E

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia. The main geography of Taiwan, island of Taiwan, also known as ''Formosa'', lies between the East China Sea, East and South China Seas in the northwestern Pacific Ocea ...

), ''T. tschonoskii'' (

Anhui Anhui is an inland Provinces of China, province located in East China. Its provincial capital and largest city is Hefei. The province is located across the basins of the Yangtze and Huai rivers, bordering Jiangsu and Zhejiang to the east, Jiang ...

Fujian Fujian is a provinces of China, province in East China, southeastern China. Fujian is bordered by Zhejiang to the north, Jiangxi to the west, Guangdong to the south, and the Taiwan Strait to the east. Its capital is Fuzhou and its largest prefe ...

Gansu Gansu is a provinces of China, province in Northwestern China. Its capital and largest city is Lanzhou, in the southeastern part of the province. The seventh-largest administrative district by area at , Gansu lies between the Tibetan Plateau, Ti ...

Hubei Hubei is a province of China, province in Central China. It has the List of Chinese provincial-level divisions by GDP, seventh-largest economy among Chinese provinces, the second-largest within Central China, and the third-largest among inland ...

Shaanxi Shaanxi is a Provinces of China, province in north Northwestern China. It borders the province-level divisions of Inner Mongolia to the north; Shanxi and Henan to the east; Hubei, Chongqing, and Sichuan to the south; and Gansu and Ningxia to t ...

Sichuan Sichuan is a province in Southwestern China, occupying the Sichuan Basin and Tibetan Plateau—between the Jinsha River to the west, the Daba Mountains to the north, and the Yunnan–Guizhou Plateau to the south. Its capital city is Cheng ...

, Tibet Autonomous Region, Yunnan,

Zhejiang ) , translit_lang1_type2 = , translit_lang1_info2 = ( Hangzhounese) ( Ningbonese) (Wenzhounese) , image_skyline = 玉甑峰全貌 - panoramio.jpg , image_caption = View of the Yandang Mountains , image_map = Zhejiang i ...

) *

India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

: ''T. govanianum'' (

Himachal Pradesh Himachal Pradesh (; Sanskrit: ''himācāl prādes;'' "Snow-laden Mountain Province") is a States and union territories of India, state in the northern part of India. Situated in the Western Himalayas, it is one of the thirteen Indian Himalayan ...

, Jammu and Kashmir,

Sikkim Sikkim ( ; ) is a States and union territories of India, state in northeastern India. It borders the Tibet Autonomous Region of China in the north and northeast, Bhutan in the east, Koshi Province of Nepal in the west, and West Bengal in the ...

Uttarakhand Uttarakhand (, ), also known as Uttaranchal ( ; List of renamed places in India, the official name until 2007), is a States and union territories of India, state in North India, northern India. The state is bordered by Himachal Pradesh to the n ...

), ''T. tschonoskii'' (Sikkim) *

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

: ''T. apetalon'', ''T. camschatcense'', ''T. channellii'' (

Hokkaido is the list of islands of Japan by area, second-largest island of Japan and comprises the largest and northernmost prefectures of Japan, prefecture, making up its own list of regions of Japan, region. The Tsugaru Strait separates Hokkaidō fr ...

), , , , ''T. smallii'', ''T. tschonoskii'', *

Korea Korea is a peninsular region in East Asia consisting of the Korean Peninsula, Jeju Island, and smaller islands. Since the end of World War II in 1945, it has been politically Division of Korea, divided at or near the 38th parallel north, 3 ...

: ''T. camschatcense'', ''T. tschonoskii'' *

Kuril Islands The Kuril Islands or Kurile Islands are a volcanic archipelago administered as part of Sakhalin Oblast in the Russian Far East. The islands stretch approximately northeast from Hokkaido in Japan to Kamchatka Peninsula in Russia, separating the ...

: ''T. apetalon'', ''T. camschatcense'', ''T. tschonoskii'' *

Myanmar Myanmar, officially the Republic of the Union of Myanmar; and also referred to as Burma (the official English name until 1989), is a country in northwest Southeast Asia. It is the largest country by area in Mainland Southeast Asia and has ...

: ''T. tschonoskii'' *

Nepal Nepal, officially the Federal Democratic Republic of Nepal, is a landlocked country in South Asia. It is mainly situated in the Himalayas, but also includes parts of the Indo-Gangetic Plain. It borders the Tibet Autonomous Region of China Ch ...

: ''T. govanianum'' *

Pakistan Pakistan, officially the Islamic Republic of Pakistan, is a country in South Asia. It is the List of countries and dependencies by population, fifth-most populous country, with a population of over 241.5 million, having the Islam by country# ...

: ''T. govanianum'' *

Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...

: ''T. apetalon'' (

Sakhalin Sakhalin ( rus, Сахали́н, p=səxɐˈlʲin) is an island in Northeast Asia. Its north coast lies off the southeastern coast of Khabarovsk Krai in Russia, while its southern tip lies north of the Japanese island of Hokkaido. An islan ...

), ''T. camschatcense'' (

Primorsky Krai Primorsky Krai, informally known as Primorye, is a federal subjects of Russia, federal subject (a krais of Russia, krai) of Russia, part of the Far Eastern Federal District in the Russian Far East. The types of inhabited localities in Russia, ...

Khabarovsk Krai Khabarovsk Krai (, ) is a federal subjects of Russia, federal subject (a krai) of Russia. It is located in the Russian Far East and is administratively part of the Far Eastern Federal District. The administrative centre of the krai is the types of ...

Kamchatka Peninsula The Kamchatka Peninsula (, ) is a peninsula in the Russian Far East, with an area of about . The Pacific Ocean and the Sea of Okhotsk make up the peninsula's eastern and western coastlines, respectively. Immediately offshore along the Pacific ...

, Sakhalin), (Sakhalin), (Primorsky Krai), ''T. smallii'' (Sakhalin), ''T. tschonoskii'' (Sakhalin) *

: ''T. taiwanense'', ''T. tschonoskii''

Identification

A fully general dichotomous key requires a mature, flowering plant. The first step is to determine whether or not the flower sits on a pedicel, which determines the subgenus. (Any mature plant may be identified to this extent, even if it is not in bloom.) Identification proceeds based on flower parts, leaves, and other characteristics. A combination of characteristics is usually required to identify the plant. Identification of a non-flowering, non-fruiting plant with bare leaves may be difficult. Although some species of ''Trillium'' have petioles (leaf stalks) and/or distinctive leaf shapes, these features are seldom sufficient to identify the plant down to the species level. In eastern North America, jack-in-the-pulpit ('' Arisaema triphyllum'') is often mistaken for bare-leaved ''Trillium''. Both species are about the same height with

trifoliate The following terms are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (that is, the leaf blade or 'lamina' is undivided) or compound (that is, the leaf blade is divided into two or more leaflets ...

leaves but the former lacks 3-way rotational symmetry and has leaf veins unlike those of ''Trillium''.

Ecology

Trilliums are myrmecochorous, that is,

ant Ants are Eusociality, eusocial insects of the Family (biology), family Formicidae and, along with the related wasps and bees, belong to the Taxonomy (biology), order Hymenoptera. Ants evolved from Vespoidea, vespoid wasp ancestors in the Cre ...

s act as agents of

seed dispersal In spermatophyte plants, seed dispersal is the movement, spread or transport of seeds away from the parent plant. Plants have limited mobility and rely upon a variety of dispersal vectors to transport their seeds, including both abiotic vectors, ...

. Each seed of a ripe fruit has a white fleshy appendage called an

. Ants are attracted to the elaiosome, so much so they often bore holes into the fruit instead of waiting for it to drop off on its own. The ants carry the seeds back to their nest where they eat the elaiosomes and discard the seeds. Here the seeds eventually germinate, an average of about 1 meter away from the parent plant. For example, the seeds of '' Trillium camschatcense'' and '' T. tschonoskii'' are collected by ant species '' Aphaenogaster smythiesi'' and '' Myrmica ruginodis''. Sometimes

beetle Beetles are insects that form the Taxonomic rank, order Coleoptera (), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 40 ...

s interfere with the dispersal process by eating the elaiosomes, which makes the seeds less attractive to ants. Yellow jackets (''

Vespula ''Vespula'' is a small genus of social wasps, widely distributed in the Northern Hemisphere. Along with members of their sister genus '' Dolichovespula'', they are collectively known by the common name yellowjackets (or yellow jackets) in North ...

'' spp.) and other wasps are similarly attracted to elaiosomes. The wasps carry off the seeds and feed on the elaiosomes an average of about 1.4 meters away from the parent plant. Yellow jackets are documented seed dispersers for at least three species of ''Trillium'' (''T. catesbaei'', ''T. cuneatum'', ''T. undulatum''). The seeds of some ''Trillium'' species are more attractive to ants than others. Widely distributed species (e.g., ''Trillium grandiflorum'', ''Trillium catesbaei'', and ''Trillium cuneatum'') are more attractive to ants than narrowly endemic species (e.g., ''Trillium lancifolium'', ''Trillium discolor'', and ''Trillium decumbens'').

Hybrids

recognizes five named hybrids, four in Asia and one in North America. Three of the Asian hybrids, , , and , are well studied, but little is known about the Asian hybrid . One of its parents is ''T. camschatcense'' but the other parent is unknown. The only named hybrid in North America is whose

was collected in

Del Norte County, California Del Norte County ( Spanish for "Of The North") is a county located at the far northwest corner of the U.S. state of California, along the Pacific Ocean adjacent to the Oregon border. Its population was 27,743 as of the 2020 census, down from ...

. As originally described, its parents are ''Trillium ovatum'' and ''Trillium rivale'', but the latter species is now a member of genus '' Pseudotrillium'', and so has become an intergeneric hybrid. In 1982, Haga and Channell crossed the Asiatic species ''Trillium camschatcense'' with several North American species. Of those, the crosses with ''T. erectum'', ''T. flexipes'', and ''T. vaseyi'' produced solid, seemingly viable seed. Seeds of the cross between ''T. camschatcense'' and ''T. erectum'' flowered in 9 to 10 years.

Disease

Trillium_grandiflorum_at_the_North_Walker_Woods1

Various ''Trillium'' species are susceptible to a greening disorder caused by bacterial organisms called

phytoplasma Phytoplasmas are obligate intracellular parasites of plant phloem tissue and of the insect vectors that are involved in their plant-to-plant transmission. Phytoplasmas were discovered in 1967 by Japanese scientists who termed them mycoplasma-li ...

s that alter the morphology of infected plants. Symptoms of phytoplasma infection include abnormal green markings on the petals (floral virescence), extra leaves ( phyllody), and other abnormal characteristics. Infected populations occur throughout the species range but are prevalent in Ontario, Michigan, and New York. For many years, this condition was thought to originate from mutation, and so many of these forms were given taxonomic names now known to be invalid. In 1971, Hooper, Case, and Meyers used

electron microscopy An electron microscope is a microscope that uses a beam of electrons as a source of illumination. It uses electron optics that are analogous to the glass lenses of an optical light microscope to control the electron beam, for instance focusing i ...

to detect the presence of mycoplasma-like organisms (i.e., phytoplasmas) in ''T. grandiflorum'' with virescent petals. The means of transmission was not established but

leafhopper Leafhopper is the common name for any species from the family (biology), family Cicadellidae: based on the type genus ''Cicadella''. These minute insects, colloquially known as hoppers, are plant feeders that suck plant sap from grass, shrubs, or ...

s were suspected. , the insect

vector Vector most often refers to: * Euclidean vector, a quantity with a magnitude and a direction * Disease vector, an agent that carries and transmits an infectious pathogen into another living organism Vector may also refer to: Mathematics a ...

for ''Trillium'' greening disorder is unknown. Phytoplasmas were positively identified in ''T. grandiflorum'' and ''T. erectum'' in Ontario in 2016.

supported the grouping of the phytoplasmas isolated from infected plants as a related strain of ' ''Candidatus'' Phytoplasma pruni' (subgroup 16SrIII-F) with 99% sequence identity. This subgroup of phytoplasmas is associated with various other diseases, including milkweed yellows, ''Vaccinium'' witches' broom, and potato purple top.

Conservation

Picking parts off a trillium plant can kill it even if the rhizome is left undisturbed. Some species of trillium are listed as threatened or endangered and collecting these species may be illegal. Laws in some jurisdictions may restrict the commercial exploitation of trilliums and prohibit collection without the landowner's permission. In the US states of

and

it is illegal to pick trilliums. In

it is illegal to pick the

red trillium ''Trillium erectum'', the red trillium, also known as wake robin, purple trillium, bethroot, or stinking benjamin, is a species of flowering plant in the family (biology), family Melanthiaceae. The plant takes its common name "wake robin" by anal ...

. In 2009, the Ontario Trillium Protection Act, a Private Members Bill, was proposed in the

legislature that would have made it illegal to in any way injure the common ''Trillium grandiflorum'' (white trillium) in the province (with some exceptions), however the bill was never passed. The rare '' Trillium flexipes'' (drooping trillium) is also protected by law in Ontario, because of its decreasing Canadian population. High

white-tailed deer The white-tailed deer (''Odocoileus virginianus''), also known Common name, commonly as the whitetail and the Virginia deer, is a medium-sized species of deer native to North America, North, Central America, Central and South America. It is the ...

population density has been shown to decrease or eliminate trillium in an area, particularly white trillium. As such height of trillium can be used as an indicator for white-tailed deer population density within forested and urban areas to help forest regeneration. Some species are harvested from the wild to an unsustainable degree. This is particularly dire in the case of ''T. govanianum'', whose high selling price as a folk medicine has motivated harvesters to destroy swathes of ecologically sensitive Himalayan forests, causing mudslides.

Medicinal uses

Several species contain

sapogenin Sapogenins are aglycones (non-saccharide moieties) of saponins, a large family of natural products. Sapogenins contain steroid or other triterpene frameworks as their key organic feature. For example, steroidal sapogenins such as tiggenin, neo ...

s. They have been used traditionally as uterine stimulants, the inspiration for the common name birthwort. In a 1918 publication, Joseph E. Meyer called it "beth root", probably a corruption of "birthroot". He claimed that an astringent tonic derived from the root was useful in controlling bleeding and diarrhea.

Culture

The white trillium (''

'') serves as the official flower and emblem of the

Canadian province Canada has ten provinces and three territories that are sub-national administrative divisions under the jurisdiction of the Constitution of Canada, Canadian Constitution. In the 1867 Canadian Confederation, three provinces of British North Amer ...

. It is an official symbol of the

Government of Ontario The Government of Ontario () is the body responsible for the administration of the Provinces and territories of Canada, Canadian province of Ontario. The term ''Government of Ontario'' refers specifically to the executive—political Minister ...

. The large white trillium is the official wildflower of Ohio. In light of their shared connection to the flower, the

Major League Soccer Major League Soccer (MLS) is a professional Association football, soccer league in North America and the highest level of the United States soccer league system. It comprises 30 teams, with 27 in the United States and 3 in Canada, and is sanc ...

teams in

Toronto Toronto ( , locally pronounced or ) is the List of the largest municipalities in Canada by population, most populous city in Canada. It is the capital city of the Provinces and territories of Canada, Canadian province of Ontario. With a p ...

and Columbus compete with each other for the Trillium Cup. Citizen scientists regularly report observations of ''Trillium'' species from around the world. ''T. grandiflorum'', ''T. erectum'', and ''T. ovatum'' (in that order) are the most often observed ''Trillium'' species. ''Trillium'' is the literary magazine of Ramapo College of New Jersey, which features poetry, fiction, photography, and other visual arts created by Ramapo students. In the 1990s, the activist Michael Page established the use of the trillium as a symbol of

bisexuality Bisexuality is romantic attraction, sexual attraction, or Human sexual activity, sexual behavior toward both males and females. It may also be defined as the attraction to more than one gender, to people of both the same and different gender, ...

, and in 2001, Francisco Javier Lagunes Gaitán and Miguel Angel Corona designed a Mexican variant of the

bisexual pride flag The bisexual flag, also called the bisexual pride flag, is a pride flag representing bisexuality, bisexual individuals and the bisexual community. According to Michael Page, the activist who created the flag based on a color palette designed ...

, which is emblazoned with an emblem of a trillium.

Gallery

File:Nodding trillium flower -SC woodlot- 3.JPG, Nodding trillium (''

'') File:Trillium petiolatum- Washington.jpg, Idaho trillium ('' Trillium petiolatum'') File:Trillium with the leaves.jpg, White trillium (''

'') File:Red trillium (42136561721).jpg, Red trillium (''

'') File:Trillium ovatum 1290.JPG, Pacific trillium ('' Trillium ovatum'') File:TrilliumRecurvatum.jpg, Prairie trillium ('' Trillium recurvatum'') File:Trillium reliquum.jpg, Relict trillium ('' Trillium reliquum)'' an

endangered species 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 ...

File:Painted Trillium.jpg, Painted trillium ('' Trillium undulatum'')

References

Bibliography

* * * * * * * * * * * * * *

External links

Interactive Identification Key
(

Java Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, proje ...

)
Utah Agricultural Experiment Station — Fact Sheets
* McKelvie, D

Ontario Woodlot Association.
Biodiversity Information Serving Our Nation (BISON) occurrence data and maps for ''Trillium''
* * * * * * * * * * {{Taxonbar, from=Q475629 Melanthiaceae genera Flora of Canada Flora of the United States Taxa named by Carl Linnaeus