Trillium (trillium, wakerobin, toadshade, tri flower, birthroot, birthwort, and sometimes "wood lily") is a genus of about fifty flowering plant species in the family Melanthiaceae. Trillium species are native to temperate regions of North America and Asia, with the greatest diversity of species found in the southern Appalachian Mountains in the southeastern United States.

Description

Plants of this genus are perennial herbs growing from rhizomes. There are three large leaf-like bracts 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 and are sometimes called leaves. The inflorescence is a single flower with three green or reddish sepals and three petals in shades of red, purple, pink, white, yellow, or green. At the center of the flower there are six stamens 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 elaiosomes.. The tetramerous 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 established the genus Trillium by recognizing three species, Trillium cernuum, Trillium erectum, and Trillium sessile. The type specimen 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. In the nineteenth and early twentieth centuries it was sometimes placed in a smaller family, Trilliaceae. By 1981 Liliaceae had grown to about 280 genera and 4,000 species. As it became clearer that the very large version of Liliaceae was polyphyletic, some botanists preferred to place Trillium and related genera into that separate family. Others defined a larger family, Melanthiaceae, 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, which assigned the genus Trillium, along with its close relative Paris, 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 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. , Plants of the World Online (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, – 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 – 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)
  • Trillium erectum – 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, – 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. The subgenus was circumscribed as a clade 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 style. They are distributed across North America (but not Asia). Flowers were and still are consumed and used by indigenous peoples in various regions of North America.

  • Trillium crassifolium – Washington
  • Trillium grandiflorum – 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 clade of seven (7) species in 2022. Species in this subgenus have pedicellate flowers (except for one variety of T. pusillum) with a definite style 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 clade 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 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 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, 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 Michigan it is illegal to pick trilliums. In New York it is illegal to pick the red trillium.

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

thumb|Ontario trillium emblem on an Ottawa courthouse sign.

The white trillium (Trillium grandiflorum) serves as the official flower and emblem of the Canadian province of Ontario. It is an official symbol of the Government of Ontario. The large white trillium is the official wildflower of Ohio. In light of their shared connection to the flower, the Major League Soccer teams in Toronto 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 1999, Michael Page established the use of the trillium flower as a symbol of bisexuality. This was a pun, as scientists had used the term "bisexual" to refer to the flower because such flowers have both male and female reproductive organs.

<gallery>

File:Nodding trillium flower -SC woodlot- 3.JPG|Nodding trillium (Trillium cernuum)

File:Trillium petiolatum- Washington.jpg|Idaho trillium (Trillium petiolatum)

File:Trillium with the leaves.jpg|White trillium (Trillium grandiflorum)

File:Red trillium (42136561721).jpg|Red trillium (Trillium erectum)

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

File:Painted Trillium.jpg|Painted trillium (Trillium undulatum)

</gallery>

References

Bibliography

  • Interactive Identification Key (Java)
  • Utah Agricultural Experiment Station — Fact Sheets
  • McKelvie, D. Woodland Plants: The Trillium. Ontario Woodlot Association.
  • Biodiversity Information Serving Our Nation (BISON) occurrence data and maps for Trillium