View source for Trillium grandiflorum

{{Short description|Species of flowering plant}}
{{redirect|White trillium}}
{{good article}}
{{Speciesbox
|image = Trillium grandiflorum at Backus Woods.jpg
|image_caption  = White trillium blooming in Backus Woods (Ontario, Canada).
|status = G5
|status_system = TNC
|status_ref = <ref name=natureserve>{{Cite web |publisher=NatureServe |title=Trillium grandiflorum |work=NatureServe Explorer |url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.152039/Trillium_grandiflorum |access-date=6 September 2019 |archive-date=23 October 2021 |archive-url=https://web.archive.org/web/20211023134346/https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.152039/Trillium_grandiflorum |url-status=live }}</ref>
|genus = Trillium
|species = grandiflorum
|authority  = ([[André Michaux|Michx.]]) [[Richard Anthony Salisbury|Salisb.]]
|synonyms = {{Collapsible list |title=''Trillium grandiflorum'' |{{Species list
  |Trillium chandleri |Farw.
  |Trillium chandleri f. foliaceum |Farw.
  |Trillium chandleri f. gladewitzii |Farw.
  |Trillium chandleri f. palaceum |Farw.
  |Trillium chandleri f. plenum |Farw.
  |Trillium chandleri f. subulatum |Farw.
  |Trillium erythrocarpum |Curtis
  |Trillium grandiflorum f. chandleri |(Farw.) Vict.
  |Trillium grandiflorum f. lirioides |(Raf.) Vict.
  |Trillium grandiflorum var. minimum |N.Coleman
  |Trillium lirioides |Raf.
  |Trillium lirioides f. albomarginatum |Farw.
  |Trillium lirioides f. giganteum |Farw.
  |Trillium lirioides var. longipetiolatum |Farw.
  |Trillium lirioides f. subsessile |Farw.
  |Trillium lirioides f. ungulatum |Farw.
  |Trillium lirioides f. variegatum |Farw.
  |Trillium liroides f. vegetum |Farw.
  |Trillium obcordatum |Raf.
  |Trillium rhomboideum var. grandiflorum |Michx.
}}}}
|synonyms_ref = {{r|POWO:542553-1}}
}}

[[File:Trillium grandiflorum clonal colony.jpg|thumb|''Trillium grandiflorum'' clonal colony]]

'''''Trillium grandiflorum''''', the '''white trillium''',{{r|USDA}} '''large-flowered trillium''', '''great white trillium''',<ref name="USFS">{{cite web |last1=Stritch |first1=Larry |title=Great White Trillium (''Trillium grandiflorum'') |url=https://www.fs.fed.us/wildflowers/plant-of-the-week/trillium_grandiflorum.shtml |publisher=[[United States Forest Service]] |access-date=1 July 2019 |archive-date=26 May 2019 |archive-url=https://web.archive.org/web/20190526165935/https://www.fs.fed.us/wildflowers/plant-of-the-week/trillium_grandiflorum.shtml |url-status=live }}</ref> '''white wake-robin''' or {{langx|fr|'''trille blanc'''}}, is a [[species]] of [[flowering plant]] in the [[family (biology)|family]] [[Melanthiaceae]]. A [[monocot]]yledonous, [[herbaceous plant|herbaceous]] [[perennial plant|perennial]], the plant is [[native plant|native]] to eastern [[North America]], from northern [[Quebec]] to the southern parts of the [[United States]] through the [[Appalachian Mountains]] into northernmost [[Georgia (U.S. state)|Georgia]] and west to [[Minnesota]]. There are also several isolated populations in [[Nova Scotia]], [[Maine]], southern [[Illinois]], and [[Iowa]].<ref>{{BONAP|ref|genus=Trillium|species=grandiflorum}}</ref>

''Trillium grandiflorum'' is most common in rich, mixed upland forests. It is easily recognised by its attractive three-petaled white flowers, opening from late spring to early summer, that rise above a [[whorl (botany)|whorl]] of three leaf-like [[bract]]s. It is an example of a [[ephemeral plant|spring ephemeral]], a plant whose life-cycle is synchronised with that of the [[deciduous]] woodland which it favours.

White trillium often occurs in dense drifts of many individuals. The [[G. Richard Thompson Wildlife Management Area]] in the [[Blue Ridge Mountains]] is renowned for an extensive stand of white trillium that blooms each spring. Over a two square mile area along the [[Appalachian Trail]] near Linden, [[Virginia]] there is a spectacular annual display of white trilliums estimated at near ten million individuals.<ref name="USFS" />

==Description==
''Trillium grandiflorum'' is a perennial that grows from a short [[rhizome]] and produces a single, showy white [[flower]] atop a whorl of three leaves. Flowering stems are 20–40&nbsp;cm tall.<ref name="Gleason">{{Cite book|last=Gleason, Henry A. (Henry Allan), 1882-1975.|url=https://www.worldcat.org/oclc/243396|title=Manual of vascular plants of Northeastern United States and adjacent Canada|others=Cronquist, Arthur.|year=1963|isbn=0-442-02722-2|location=Princeton, N.J.|page=211|oclc=243396|access-date=2020-12-30|archive-date=2021-11-10|archive-url=https://web.archive.org/web/20211110071907/https://www.worldcat.org/title/manual-of-vascular-plants-of-northeastern-united-states-and-adjacent-canada/oclc/243396|url-status=live}}</ref> The leaves are often called [[bract]]s as the "stem" is then considered a [[peduncle (botany)|peduncle]] (the rhizome is the stem proper, aboveground shoots of a rhizome are branches or peduncles); the distinction between bracts (found on pedicels or peduncles) and leaves (borne on stems).{{sfnp|Case|Case|1997|p=99}} A single rootstock will often form [[clonal colonies]], which can become very large and dense.{{sfnp|Case|Case|1997|p=50}}
[[File:White Trillium Trillium grandiflorum Leaf Closeup 2500px.JPG|right|thumb|Detail of a leafy [[bract]] showing engraved venation]]
The erect, odorless flowers are large, especially compared to other species of ''Trillium'', with {{convert|4|to|7|cm|in|round=0.5|abbr=on}} long [[petal]]s, depending on age and vigor. The petals are shaped much like the leaves and curve outward. They have a visible venation, though this is not as heavily marked as on the leaves. Their overlapping bases and curve give the flowers a distinctive [[funnel]] shape. Between the veined petals, three acuminate (ending with a long point) [[sepal]]s are visible; they are usually a paler shade of green than the leaves, and are sometimes streaked with maroon. The flowers are perched on a [[Pedicel (botany)|pedicel]] (i.e., flower stalk) raising them above the leaf whorl, and grow pinker as they age.{{sfnp|Case|Case|1997|p=104}}{{r|FNA}} The flowers' stigmas are slender, straight or mostly so, narrowing at the end.<ref name="Gleason"/> The white petals are much longer than the green sepals.<ref name="Gleason"/> The flowers have six [[stamen]]s in two whorls of three, which [[marcescence|persist]] after fruiting. The [[Gynoecium|style]]s are white and very short compared to the {{convert|9|–|27|mm|in|abbr=on}} [[anther]]s, which are pale yellow, but become a brighter shade when liberating [[pollen]] due to the latter's color. The [[Ovary (plants)|ovaries]] are six-sided with three greenish-white stigmas that are at first weakly attached, but fuse higher up. The fruit is a green, mealy and moist orb, and is vaguely six-sided like the ovary.{{sfnp|Case|Case|1997|p=104}}{{r|FNA}}

==Taxonomy==
''Trillium grandiflorum'' was first described by [[André Michaux]] in 1803 as variety ''grandiflorum'' of ''Trillium rhomboideum'',{{r|IPNI:258372-2}} a species now regarded as a [[Synonym (taxonomy)|synonym]] of ''Trillium erectum'' var.&nbsp;''erectum''.{{r|POWO:328449-2}} Michaux described the variety as having broadly rhombic leaves, large white petals, and black fruit.{{r|Michaux 1803}} The epithet ''grandiflorum'' means "large-flowered",{{sfnp|Gledhill|2008|p=104}} a name that well describes Michaux's variety. In 1805, [[Richard Anthony Salisbury]] elevated the variety to a full species.{{r|IPNI:542553-1}}{{r|Hooker 1805}} As a consequence, and partially by accident, ''Trillium grandiflorum'' is commonly known as the '''large-flowered white trillium'''.{{sfnp|Case|Case|1997|p=104}}

{{As of|March 2023}}, the name ''Trillium grandiflorum'' {{small|(Michx.) Salisb.}}&nbsp;is widely recognized.{{r|POWO:542553-1|USDA|FNA|VASCAN}} The species is a member of the [[Trillium#Subgenus Callipetalon|Grandiflorum group]], a group of species typified by ''Trillium grandiflorum'' itself.{{sfnp|Lampley|Gereau|Floden|Schilling|2022|p=281}} The group, which also includes ''Trillium nivale'' and ''Trillium ovatum'', is [[Sister group|sister]] to a [[clade]] comprising [[Trillium#Subgenus Sessilia|subgenus ''Sessilia'']] (the sessile-flowered trilliums) and [[Trillium#Subgenus Delostylis|subgenus ''Delostylis'']] (the Catesbaei group).{{sfnp|Lampley|2021|pp=42}}

[[File:Trillium grandiflorum pink1.jpg|right|thumb|''Trillium grandiflorum'' forma ''roseum'' with distinctly undulate margin of petals and leaves]]

{{As of|November 2021}}, [[Plants of the World Online]] (POWO) lists 20&nbsp;synonyms for ''Trillium grandiflorum''.{{r|POWO:542553-1}} Although POWO accepts no [[infraspecific name]]s, numerous varieties and forms have been described. Of these, perhaps the best known is ''Trillium grandiflorum'' f.&nbsp;''roseum'' {{small|Farw.}},{{sfnp|Case|Case|1997|pp=107-108}}{{r|FNA}} which was described by [[Oliver Atkins Farwell]] in 1920.{{r|goldsword}} The flower of forma ''roseum'' opens a striking salmon-pink instead of the more typical white. The pink color of the form is warmer and more attractive than the pink induced by aging. It occurs rarely throughout the range of the species, except along the [[Blue Ridge Mountains]] of [[Virginia]] where it is locally frequent.{{sfnp|Case|Case|1997|pp=109-110}} The epithet ''roseum'' means "rose-like, rose-colored",{{sfnp|Gledhill|2008|p=334}} and so the form is sometimes called the '''rose trillium'''.

''Trillium grandiflorum'', unlike most trilliums, occasionally produces [[double-flowered]] forms with more than three petals. ''T.&nbsp;grandiflorum'' f.&nbsp;''polymerum'' {{small|Vict.}}, a multipetaled form described by [[Marie-Victorin Kirouac]] in 1929,{{r|goldsword}} occurs rather frequently in this species.{{sfnp|Case|Case|1997|pp=107-108}} Although these wild forms are stable and healthy, the plants usually lack normal floral organs and are therefore completely sterile. The epithet ''polymerum'' means "many-parts",{{sfnp|Gledhill|2008|pp=257,309}} which in this case refers to the many flower petals of the form.

Some variants of ''Trillium grandiflorum'' have abnormal green markings on the petals (floral [[virescence]]), floral organs that take on a leaf-like appearance ([[phyllody]]), or other abnormal characteristics. Many of these forms have been given taxonomic names with epithets such as ''albomarginatum'' ("white-margined", referring to the petals), ''foliaceum'', ("leaf-like, leafy"), ''giganteum'' ("unusually large or tall"), and ''longipetiolatum'' ("with long petioles").{{r|POWO:542553-1}} A typical example is the variety ''Trillium grandiflorum'' var.&nbsp;''variegatum'' {{small|E.F.Sm.}}, described by [[Erwin Frink Smith]] in 1879.{{r|goldsword|IPNI:1093416-2}} The epithet ''variegatum'' ("streaked or spotted with color") refers to its virescent petals, a distinguishing characteristic of this variety. In 1971, it was shown that mycoplasma-like organisms (now called [[phytoplasma]]s) were present in all such forms examined (but not in normal plants). The authors concluded that "such plants should now be regarded as diseased ''T.&nbsp;grandiflorum'' and the varietal designation of Smith should be considered invalid."{{r|Hooper et al. 1971}}

Unlike other species such as ''Trillium erectum'', which hybridize fairly easily, ''Trillium grandiflorum'' is not known to form hybrids.{{sfnp|Case|Case|1997|p=108}}

==Ecology==
''Trillium grandiflorum'' favors well-drained, neutral to slightly [[acid soil]]s, usually in second- or young-growth forests. In the Northern parts of its range it shows an affinity for [[maple]] or [[beech]] forests, but has also been known to spread into nearby open areas. Depending on geographical factors, it flowers from late April to early June, just after ''Trillium erectum''.<ref>Lamoureux, ''Flore Printanière'', p. 48.</ref>{{sfnp|Case|Case|1997|pp=44,106-107}} Like many forest [[perennial plant|perennial]]s, ''Trillium grandiflorum'' is a slow growing plant. Its seeds have double dormancy, meaning they normally take at least two years to fully [[germination|germinate]]. The seeds are dispersed in late summer, germinating after a cold and then a warm period, producing a root and after another winter the seedling's cotyledon emerges from the soil.<ref name="BaskinBaskin2014">{{cite book|author1=Carol C. Baskin|author2=Jerry M. Baskin|title=Seeds: Ecology, Biogeography, and, Evolution of Dormancy and Germination|url=https://books.google.com/books?id=CYO-AQAAQBAJ&pg=PA136|date=20 February 2014|publisher=Elsevier|isbn=978-0-12-416683-7|pages=136–|access-date=1 October 2018|archive-date=10 November 2021|archive-url=https://web.archive.org/web/20211110071907/https://books.google.com/books?id=CYO-AQAAQBAJ&pg=PA136|url-status=live}}</ref> Like most species of ''Trillium'', flowering age is determined largely by the surface of the leaf and size of the rhizome instead of age alone. Because growth is very slow in nature, ''T. grandiflorum'' typically requires seven to ten years in optimal conditions to reach flowering size, which corresponds to a minimum of {{convert|36|cm2|sqin|abbr=on}} of leaf surface area and {{convert|2.5|cm3|cuin|abbr=on}} of rhizome volume.<ref>Lamoureux, ''Flore Printanière'', pp. 429-430.</ref> In cultivation, however, wide disparity of flowering ages are observed.{{sfnp|Case|Case|1997|pp=30-31}}

===Pollination and seed dispersal===
''Trillium grandiflorum'' has long been thought to self-pollinate based on the fact that pollinators had rarely been observed visiting the plants and because there is low variation in chromosomal banding patterns. This has been strongly challenged, as other studies have shown high pollination rates by [[bumblebee]]s and very low success of self-pollination in controlled experiments, implying that they are in fact self-incompatible.<ref name=ants/> Several [[ovule]]s of a given individual often fail to produce seeds. One contributing factor is pollen limitation, and one study showed that open pollinated plants had 56% of their ovules produce seeds, while in hand pollinated individuals the figure was 66%. Plants with reduced exposure to pollinators were 33% to 50% less likely to produce fruits than those that were, while hand pollinated individuals showed a 100% fruit set (though these fruits did not contain a 100% seed set). Plant resources were shown to be a limiting factor in seed production: when pollen was in abundance, larger plants had a significantly greater seed to ovule ratio than smaller ones. The overall suboptimal seed to ovule ratios suggest that ''Trillium grandiflorum'' has evolved to maximize reproductive success in the face of highly [[stochastic]] pollination, where some plants may only be visited by a single pollinator in a season.<ref>{{Cite journal| last1=Griffin| first1=Steven R.| title=Factors Affecting Low Seed: Ovule Ratios in a Spring Woodland Herb, Trillium grandiflorum (Melanthiaceae)| journal=International Journal of Plant Sciences| volume=163| year=2002| pages=581–590| doi=10.1086/340814| issue=4| last2=Barrett| first2=Spencer C. H.| s2cid=5018803}}</ref>

''Trillium grandiflorum'' has been studied extensively by ecologists due to a number of unique features it possesses. It is a representative example of a plant whose seeds are spread through [[myrmecochory]], or ant-mediated dispersal, which is effective in increasing the plant's ability to [[outcross]], but ineffective in bringing the plant very far. This has led ecologists to question how it and similar plants were able to survive glaciation events during the ice ages. The height of the species has also been shown to be an effective index of how intense foraging by deer is in a particular area.

[[File:White Trillium Trillium grandiflorum Flower 2613px.jpg|right|thumb|Detail of flower showing 6&nbsp;[[stamen]]s, 3&nbsp;[[Stigma (botany)|stigma]]s, and petals with deep veins]]

Fruits are released in the summer, containing about 16 seeds on average. These seeds are most typically dispersed by [[ant]]s, which is called [[myrmecochory]], but yellow jackets (''[[Vespula vulgaris]]'') and [[harvestmen]] (order Opiliones) have both been observed dispersing the seeds at lower frequencies. Insect dispersal is aided by the presence of a conspicuous [[elaiosome]], an oil-rich body attached to the seed, which is high in both [[lipid]]s and [[oleic acid]]. The oleic acid induces corpse-carrying behavior in ants, causing them to bring the seeds to their nesting sites as if they were food. As ants visit several colonies of the plant, they bring genetically variable seeds back to a single location, which after germination results in a new population with relatively high [[genetic diversity]]. This has the ultimate effect of increasing [[biological fitness]].<ref name=ants>{{cite journal| title=Ant-Mediated Seed Dispersal Alters Pattern of Relatedness in a Population of Trillium grandiflorum| last=Kalisz| first=Susan|author2= Hanzawa, Frances M.|author3= Tonsor, Stephen J.|author4= Thiede, Denise A.|author5= Voigt, Steven| journal=Ecology| volume=80| year=1999| pages=2620–2634 |doi=10.1890/0012-9658(1999)080[2620:AMSDAP]2.0.CO;2| issue=8}}</ref>

Although myrmecochory is by far the most common dispersal method, [[white-tailed deer]] have also been shown to disperse the seeds on rare occasions by ingestion and defecation. While ants only move seeds up to about 10 meters, deer have been observed to transport the seeds over 1 kilometer. This helps to explain post-agricultural colonization of forest sites by ''Trillium grandiflorum'', as well as long distance [[gene flow]] which has been detected in other studies. Furthermore, it helps resolve what has been called "[[Reid's paradox]]", which states that migration during [[Glacial motion|glaciation events]] must have been impossible for plants with dispersal rates under several hundred meters per year, such as ''Trillium grandiflorum''. Thus occasional long distance dispersal events, such as by deer, probably helped save this and other species with otherwise short distance dispersal ability from extinction during the glaciations of the [[ice ages]].<ref>{{Cite journal| title=Dispersal of ''Trillium'' Seeds by Deer: Implications for Long-Distance Migration of Forest Herbs| last1=Vellend| first1=Mark; Myers, Jonathan A.; Gardescu, Sana; Marks, P.L.| journal=Ecology| volume=84| year=2003| url=http://www3.botany.ubc.ca/vellend/Vellend_et_al_Tg_Deer_Ecol_2003.pdf| pages=1067–1072| doi=10.1890/0012-9658(2003)084[1067:DOTSBD]2.0.CO;2| issue=4| last2=Myers| first2=Jonathan A.| last3=Gardescu| first3=Sana| last4=Marks| first4=P. L.| access-date=2008-04-23| archive-date=2009-03-26| archive-url=https://web.archive.org/web/20090326141924/http://www3.botany.ubc.ca/vellend/Vellend_et_al_Tg_Deer_Ecol_2003.pdf| url-status=live}}</ref> Furthermore, nested [[clade]] analysis of [[cpDNA]] [[haplotypes]] has shown that ''Trillium grandiflorum'' is likely to have persisted through the [[last glacial period]] in two sites of refuge in the southeastern [[United States]] and that long distance dispersal was responsible for the post-glacial recolonization of northern areas.<ref>{{Cite journal| last=Griffin| first=Steven R.| title=Post-glacial history of ''Trillium grandiflorum'' (Melanthiaceae) in eastern North America: inferences from phylogeography| journal=American Journal of Botany| year=2004| volume=91| pages=465–473| doi=10.3732/ajb.91.3.465| issue=3| pmid=21653402| s2cid=207683617| doi-access=free}}</ref>

In addition to the lateral dispersion (by invertebrates and deer) there is also importance in the fact that burial (vertical dispersion) by ants (or other vectors) increases the survival of new plants by two mechanisms. First, vertical dispersion ensures sufficient depth to preserve the seeds through their dormancy (trillium seeds are normally dormant for their first year). Second, vertical dispersion ensures adequate anchorage of the rhizomes. This is particularly important for young plants because their small rhizomes, with few & short roots, are easily dislodged (e.g. frost heaveal and other erosion factors) and desiccated.<ref>Lampe, pers. com. 2013</ref>

===Interaction with deer===
''Trillium grandiflorum'' as well as other trilliums are a favored food of [[white-tailed deer]]. Indeed, if trilliums are available deer will seek these plants, with a preference for ''T. grandiflorum'', to the exclusion of others.<ref>Lamoureux, ''Flore printanière'', p. 441.</ref> In the course of normal browsing, deer consume larger individuals, leaving shorter ones behind. This information can be used to assess deer density and its effect on understory growth in general.<ref name="anderson">{{Cite journal| last=Anderson| first=Roger C.| title=Height of White-Flowered Trillium (Trillium Grandiflorum) as an Index of Deer Browsing Intensity| journal=Ecological Applications| volume= 4 | year=1994 | pages=104–109| doi=10.2307/1942119| issue=1| jstor=1942119}}</ref><ref name="koh">{{Cite journal| last1=Koh| first1=Saewan|author-link2=Dawn R. Bazely|last2=Bazely|first2=Dawn R.|last3=Tanentzap|first3=Andrew J.|last4=Voigt|first4=Dennis R.|last5=Da Silva|first5=E.| title=Trillium grandiflorum height is an indicator of white-tailed deer density at local and regional scales| journal=Forest Ecology and Management| volume= 259 | issue=8| year=2010 | pages=1472–1479| doi=10.1016/j.foreco.2010.01.021}}</ref>

When foraging intensity increases, individuals become shorter each growing season due to the reduction in energy reserves from less photosynthetic production. One study determined that the ideal deer density in northeastern [[Illinois]], based on ''T. grandiflorum'' as an indicator of overall understory health, is 4 to 6 animals per square kilometer. This is based on a 12 to 14&nbsp;cm stem height as an acceptable healthy height.<ref name="anderson"/> In practice, deer densities as high as 30 deer per square kilometers are known to occur in restricted or fractured habitat where natural control mechanisms (that is, [[predator]]s like [[Gray wolf|wolves]]) are lacking. Such densities, if maintained over more than a few years, can be very damaging to the understory and lead to extinction of some local understory plant populations.<ref name="koh"/>{{sfnp|Case|Case|1997|p=60}}<ref>Lamoureux, ''Flore printanière'', pp. 395, 441-443.</ref>

===Disease===
[[File:Trillium_grandiflorum_at_the_North_Walker_Woods1.jpg|thumb|Diseased ''T. grandiflorum'' with virescent petals, extra petals, and other abnormalities]]
''Trillium grandiflorum'' is susceptible to a greening disorder caused by bacterial organisms called [[phytoplasma]]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.{{r|Case 1994}} Infected populations occur throughout the species range but are prevalent in Ontario, Michigan, and New York.{{r|Gates 1917}}

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 microscope|electron microscopy]] to detect the presence of mycoplasma-like organisms (i.e., phytoplasmas) in ''T.&nbsp;grandiflorum'' with virescent petals. The means of transmission was not established but [[leafhopper]]s were suspected.{{r|Hooper et al. 1971}} {{As of|November 2021}}, the insect [[Disease vector|vector]] for the disorder is unknown.

Phytoplasmas were positively identified in ''T.&nbsp;grandiflorum'' and ''T.&nbsp;erectum'' in Ontario in 2016 and later confirmed in 2019. [[Phylogenetics|Phylogenetic analysis]] supported the grouping of the phytoplasmas isolated from infected plants as a related strain of '[[Candidatus Phytoplasma pruni|''Candidatus'' Phytoplasma pruni]]' (subgroup 16SrIII-F) with 99% sequence identity.{{r|Arocha-Rosete et al. 2016}} This subgroup of phytoplasmas is associated with various other diseases, including [[Milkweed yellows phytoplasma#Milkweed yellows|milkweed yellows]], ''Vaccinium'' [[witches' broom]], and potato purple top.{{r|Davis et al. 2013}}

==Conservation==
Some [[subspecies|forms]] of the species have pink instead of white petals, while others with extra petals, also called "double" forms, are naturally quite common in the species, and these are especially popular with trillium gardeners. In fact, the species is the most popular of its genus in cultivation, which has led to conservation concerns due to the majority of commercially available plants being collected from the wild. A few regional governments in Canada and the United States have declared the plant vulnerable as a result. In [[Quebec]], ''Trillium grandiflorum'' is legally listed as vulnerable primarily due to habitat destruction in forests neighboring the province's most populous regions.<ref>{{cite web |title=Trille blanc |url=http://www.mddep.gouv.qc.ca/biodiversite/especes/trille/index.htm |publisher=Ministère du Développement durable, de l'Environnement et des Parcs du Québec |year=2005 |work=Plantes menacées ou vulnérables au Québec |access-date=2007-04-23 |language=fr |archive-date=2012-09-04 |archive-url=https://archive.today/20120904162538/http://www.mddep.gouv.qc.ca/biodiversite/especes/trille/index.htm |url-status=live }}</ref> In New York, ''Trillium grandiflorum'' is exploitably vulnerable since it is "likely to become threatened in the near future throughout all or a significant portion of its range within the state if causal factors continue unchecked" (NYCRR §193.3).{{Citation needed|date=November 2021}}

Due to the popularity of ''Trillium grandiflorum'' as a garden specimen, conservation concerns have been raised as the vast majority of plants sold in commercial nurseries are believed to be collected from the wild. Indeed, there is little indication of any commercial nursery growth. Frederick and Roberta Case, botanists who specialize in trilliums, wrote in 1997,{{sfnp|Case|Case|1997|p=61}} "to our knowledge, no true commercial quantity 'propagation' takes place at the present time." Such heavy collecting, combined with other pressures such as habitat destruction and grazing, may effectively endanger the plants in some areas.<ref name="Lamoureux, pp. 437-443">Lamoureux, ''Flore printanière'', pp. 437-443.</ref>{{sfnp|Case|Case|1997|pp=49,59-64}}

{{As of|October 2019}}, ''Trillium grandiflorum'' is globally secure.{{r|natureserve}} The species is vulnerable in Quebec, Georgia, and Illinois; and critically imperiled in Nova Scotia, Alabama, New Jersey, and South Carolina. In [[Maine]], where its presence has not been verified in over 20&nbsp;years, ''Trillium grandiflorum'' is listed as potentially [[Local extinction|extirpated]].<ref>{{cite web |title=''Trillium'' grandiflorum {{small|(Michx.) Salisb.}}: Large White Trillium |url=https://www.maine.gov/dacf/mnap/features/trigra.htm |publisher=Maine Natural Areas Program |access-date=3 November 2021 |archive-date=18 October 2020 |archive-url=https://web.archive.org/web/20201018135300/https://www.maine.gov/dacf/mnap/features/trigra.htm |url-status=live }}</ref>

==Cultivation==
[[File:Double Trillium grandiflorum.jpg|thumb|Double-flowered forms of ''T. grandiflorum'' are sought after by trillium enthusiasts]]
''Trillium grandiflorum'' is one of the most popular trilliums in cultivation, primarily because of the size of its flowers and its relative ease of cultivation. Although not particularly demanding, its cultivation is a slow and rather uncertain process, due to usually slow growth, wide variations in growth speed and sometimes capricious germination rates. As a result, the vast majority of plants and rhizomes in commerce are collected in the wild, and such heavy collecting, combined with other pressures such as habitat destruction and grazing, may effectively endanger the plants in some areas. This also creates tensions between Trillium enthusiasts and conservation proponents.<ref name="Lamoureux, pp. 437-443"/>{{sfnp|Case|Case|1997|pp=49,59}} Transplantation (as with almost all non-weedy wild plants) is a delicate process, and in many cases results in the death of the plant.<ref name="thestar"/> In cultivation, ''T. grandiflorum'' may flower in as little as 4 to 5 years after germination (compared to the usual 7 to 10 in the wild), but these cases appear to be exceptions rather than the rule. One study revealed 20 or so individuals performing so well out of about 10,000 seeds planted, only 20% of which germinated after a year. However, barring plant destruction, ''T. grandiflorum'' can continue flowering every year after it has begun.{{sfnp|Case|Case|1997|pp=29-31,46-52}} It is winter hardy in [[Hardiness zone|USDA zone]]s 4-8.<ref>{{Cite web|title=Trillium grandiflorum - Plant Finder|url=https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=f317|access-date=2020-12-30|website=www.missouribotanicalgarden.org|archive-date=2020-11-12|archive-url=https://web.archive.org/web/20201112024323/http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=f317|url-status=live}}</ref>

A double-flowered cultivar, [[Trillium grandiflorum 'Pamela Copeland'|''T.&nbsp;grandiflorum'' 'Pamela Copeland']], was introduced to cultivation at the [[Mount Cuba Center]] and named for Mrs. [[Pamela du Pont Copeland]], the center's founder.<ref>{{Cite news|url=https://www.washingtonpost.com/wp-dyn/content/article/2008/04/23/AR2008042300815.html|title=Pamela Copeland Large-Flowered Trillium - Mt. Cuba Center|newspaper=Mt. Cuba Center|language=en-US|access-date=2017-01-27|archive-date=2017-02-02|archive-url=https://web.archive.org/web/20170202065537/http://www.washingtonpost.com/wp-dyn/content/article/2008/04/23/AR2008042300815.html|url-status=live}}</ref>

This plant has gained the [[Royal Horticultural Society]]'s [[Award of Garden Merit]].<ref name = RHSPF>{{cite web | url = https://www.rhs.org.uk/Plants/18385/Trillium-grandiflorum/Details | title = ''Trillium grandiflorum'' | website = www.rhs.org | publisher = Royal Horticultural Society | access-date = 12 April 2020 | archive-date = 21 January 2021 | archive-url = https://web.archive.org/web/20210121045930/https://www.rhs.org.uk/plants/18385/Trillium-grandiflorum/Details | url-status = live }}</ref>

==Uses==
The leaves were cooked and eaten by some [[Native Americans in the United States|Native Americans]]. The subterranean rootstalks were also chewed for various medical purposes.<ref>{{cite book |last1=Niering |first1=William A. |author-link1=William Niering| last2=Olmstead |first2=Nancy C. |title=The Audubon Society Field Guide to North American Wildflowers, Eastern Region |year=1985 |orig-year=1979|publisher=Knopf |isbn=0-394-50432-1 |page=611}}</ref>

==Culture==
The large white trillium is a well-known and popular American flower.{{r|Case 1994}} The ''Trillium'' species most often observed by [[Citizen science|citizen scientists]] is ''T.&nbsp;grandiflorum''.<ref>{{cite web |title=Citizen science observations of ''Trillium'' species |url=https://www.inaturalist.org/observations?place_id=any&taxon_id=49465&view=species |publisher=[[iNaturalist]] |access-date=1 September 2019 |archive-date=10 November 2021 |archive-url=https://web.archive.org/web/20211110071916/https://www.inaturalist.org/observations?place_id=any&taxon_id=49465&view=species |url-status=live }}</ref>

The flower's common name, wake-robin, was the title of American naturalist and essayist [[John Burroughs|John Burroughs's]] first essay collection, ''Wake-Robin.''<ref>{{Cite book|last=Burroughs|first=John|title=Wake-Robin|publisher=Houghton, Mifflin & Co.|year=1871|location=New York, NY}}</ref>

[[File:Franco-Ontarian flag.svg|thumb|The official flag of Ontario's French-speaking minority, the [[Franco-Ontarian]]s, incorporates a stylized trillium representing Ontario and a [[fleur-de-lis]] representing French Canadian heritage.]]

As a particularly conspicuous forest flower, ''T. grandiflorum'' was designated the provincial floral emblem of [[Ontario]] in 1937 (Floral Emblem Act),<ref>{{cite web|title=Emblems and Symbols |url=http://www.gov.on.ca/ont/portal/!ut/p/.cmd/cs/.ce/7_0_A/.s/7_0_252/_s.7_0_A/7_0_252/_l/en?docid=EC001037 |publisher=Government of Ontario |access-date=2007-04-23 |archive-url=https://web.archive.org/web/20070311064349/http://www.gov.on.ca/ont/portal/%21ut/p/.cmd/cs/.ce/7_0_A/.s/7_0_252/_s.7_0_A/7_0_252/_l/en?docid=EC001037 |archive-date=2007-03-11 |url-status=dead }}</ref><ref>{{cite web |title=Ontario's provincial symbols |date=15 August 2017 |url=https://www.canada.ca/en/canadian-heritage/services/provincial-territorial-symbols-canada/ontario.html |publisher=Government of Canada |access-date=10 December 2019 |archive-date=12 September 2019 |archive-url=https://web.archive.org/web/20190912201706/https://www.canada.ca/en/canadian-heritage/services/provincial-territorial-symbols-canada/ontario.html |url-status=live }}</ref> and as the [[List of U.S. state flowers|state wild flower]] of [[Ohio]] in 1987.<ref>{{cite web |title=Ohio State Wildflower |url=http://www.netstate.com/states/symb/wildflowers/oh_large_white_trillium.htm |publisher=Netstate |access-date=2007-04-23 |archive-date=2007-06-02 |archive-url=https://web.archive.org/web/20070602184902/http://www.netstate.com/states/symb/wildflowers/oh_large_white_trillium.htm |url-status=live }}</ref> Professional soccer teams from [[Toronto]] and [[Columbus, Ohio|Columbus]] compete for the [[Trillium Cup]] every year.

As an official [[Symbols of Ontario|symbol of Ontario]], a stylized trillium flower features prominently in the [[wordmark]] of the [[Government of Ontario]] and on the official flag of [[Franco-Ontarian|the province's French-speaking minority]].<ref>{{cite web |title=Franco-Ontarian Flag |url=http://www.ofa.gov.on.ca/english/commun-flag.html |publisher=Ontario Office of Francophone Affairs |access-date=2007-04-23 |url-status=dead |archive-url=https://web.archive.org/web/20070420164718/http://www.ofa.gov.on.ca/english/commun-flag.html |archive-date=2007-04-20 }}</ref> Government agencies and programs also frequently incorporate the word "trillium" in their names, such as the [[Trillium Gift of Life Network]] ([[organ donation]] management agency) and the [[Trillium Book Award]] (an annual [[literary award]] sponsored by the provincial government). It is also frequently used by the [[Canadian Heraldic Authority]] to represent Ontario in grants of arms.<ref>For examples see [https://wayback.archive-it.org/all/20080503200829/http://www.gg.ca/heraldry/pub-reg/project-pic.asp?ProjectID=20&ProjectElementID=51 here] or [https://wayback.archive-it.org/all/20080503200844/http://www.gg.ca/heraldry/pub-reg/project-pic.asp?ProjectID=41&ProjectElementID=119 here].</ref> Although a network of laws make picking wildflowers illegal in the province on any Crown or provincially owned land, it is not, unlike widely believed, specifically illegal (or necessarily harmful) to pick the species in Ontario.<ref name="thestar">{{cite news |last=Bhattacharya |first=Surya |title='The herb true love of Canada': What you need to know about our now-blooming flower emblem, including the answer to the big question |url=https://www.thestar.com/article/213271 |date=May 13, 2007 |newspaper=[[Toronto Star]] |access-date=2007-04-23 |archive-date=2007-09-29 |archive-url=https://web.archive.org/web/20070929170729/http://www.thestar.com/article/213271 |url-status=live }}</ref>

==References==
{{Reflist|40em|refs=
<ref name="Arocha-Rosete et al. 2016">{{cite journal |last1=Arocha-Rosete |first1=Y. |last2=Morales-Lizcano |first2=N.P. |last3=Hasan |first3=A. |last4=Yoshioka |first4=K. |last5=Moeder |first5=W. |last6=Michelutti |first6=R. |last7=Satta |first7=E. |last8=Bertaccini |first8=A. |last9=Scott |first9=J. |title=First report of the identification of a {{'}}''Candidatus'' Phytoplasma pruni'-related strain in ''Trillium'' species in Canada |journal=New Disease Reports |date=2016 |volume=34 |page=19 |doi=10.5197/j.2044-0588.2016.034.019|doi-access=free }}</ref>
<ref name="Case 1994">{{cite journal |last1=Case  |first1=Frederick W. Jr.|title=''Trillium grandiflorum'': Doubles, Forms, and Diseases |journal=Bulletin of the American Rock Garden Society |date=Winter 1994 |volume=52 |issue=1 |pages=40–49 |url=https://nargs.org/sites/default/files/free-rgq-downloads/VOL_52_NO_1.pdf |access-date=5 November 2021 |archive-date=1 September 2019 |archive-url=https://web.archive.org/web/20190901135312/https://nargs.org/sites/default/files/free-rgq-downloads/VOL_52_NO_1.pdf |url-status=live }}</ref>
<ref name="Davis et al. 2013">{{cite journal |last1=Davis |first1=R.E. |last2=Zhao |first2=Y. |last3=Dally |first3=E.L. |last4=Lee |first4=I.M. |last5=Jomantiene |first5=R. |last6=Douglas |first6=S.M. |title={{'}}''Candidatus'' Phytoplasma pruni', a novel taxon associated with X-disease of stone fruits, ''Prunus'' spp.: multilocus characterization based on 16S rRNA, secY, and ribosomal protein genes |journal=Int J Syst Evol Microbiol |date=2013 |volume=63 |issue=Pt 2 |pages=766–776 |doi=10.1099/ijs.0.041202-0 |pmid=22798643}}</ref>
<ref name="FNA">{{eFloras |1 |242101995 |Trillium grandiflorum |volume=26 |last=Case Jr. |first=Frederick W.}}</ref>
<ref name="Gates 1917">{{cite journal |last1=Gates |first1=R.R. |title=A systematic study of the North American genus ''Trillium'', its variability, and its relation to ''Paris'' and ''Medeola'' |journal=Annals of the Missouri Botanical Garden |date=February 1917 |volume=4 |issue=1 |pages=43–92 |doi=10.2307/2990062 |jstor=2990062 |url=https://www.biodiversitylibrary.org/item/54259#page/51/mode/1up |access-date=28 October 2021 |archive-date=28 October 2021 |archive-url=https://web.archive.org/web/20211028150443/https://www.biodiversitylibrary.org/item/54259#page/51/mode/1up |url-status=live }}</ref>
<ref name="goldsword">{{cite web |last1=Farmer |first1=Susan B. |title=Named Trilliaceae taxa sorted by genus and species name |url=http://www.goldsword.com/sfarmer/Trillium/trillium-genus.html |website=goldsword.com |access-date=4 November 2021 |archive-date=4 November 2021 |archive-url=https://web.archive.org/web/20211104155733/http://www.goldsword.com/sfarmer/Trillium/trillium-genus.html |url-status=live }}</ref>
<ref name="Hooker 1805">{{cite book |last1=Hooker |first1=William |title=The Paradisus Londinensis: or Coloured Figures of Plants Cultivated in the Vicinity of the Metropolis |date=1805 |location=London |at=Tab.&nbsp;1 |url=https://www.biodiversitylibrary.org/page/36898142#page/3/mode/1up |access-date=2 November 2021 |archive-date=2 November 2021 |archive-url=https://web.archive.org/web/20211102223927/https://www.biodiversitylibrary.org/page/36898142#page/3/mode/1up |url-status=live }}</ref>
<ref name="Hooper et al. 1971">{{cite journal |last1=Hooper |first1=G. R. |last2=Case  |first2=F. W. Jr.|last3=Myers |first3=R. |title=Mycoplasma-like bodies associated with a flower greening disorder of a wild flower, ''Trillium grandiflorum'' |journal=Plant Disease Reporter |date=1971 |volume=55 |pages=824–828 |url=https://books.google.com/books?id=C9FRLr8RA2AC&pg=PA1108 |access-date=7 November 2021 |archive-date=10 November 2021 |archive-url=https://web.archive.org/web/20211110071908/https://books.google.com/books?id=C9FRLr8RA2AC&pg=PA1108 |url-status=live }}</ref>
<ref name="IPNI:258372-2">{{IPNI |id=258372-2 |taxon=Trillium rhomboideum var. grandiflorum |authority={{small|Michx.}} |access-date=2 November 2021}}</ref>
<ref name="IPNI:542553-1">{{IPNI |id=542553-1 |taxon=Trillium grandiflorum |authority={{small|(Michx.) Salisb.}} |access-date=4 November 2021}}</ref>
<ref name="IPNI:1093416-2">{{IPNI |id=1093416-2 |taxon=Trillium grandiflorum var. variegatum |authority={{small|E.F.Sm.}} |access-date=7 November 2021}}</ref>
<ref name="Michaux 1803">{{cite journal |last1=Michaux |first1=André |title=''Trillium rhomboideum'' |journal=Flora Boreali-Americana |date=1803 |volume=1 |pages=215–216 |url=https://www.biodiversitylibrary.org/page/404989#page/249/mode/1up |access-date=2 November 2021 |archive-date=31 October 2021 |archive-url=https://web.archive.org/web/20211031170136/https://www.biodiversitylibrary.org/page/404989#page/249/mode/1up |url-status=live }}</ref>
<ref name="POWO:328449-2">{{cite web |title=''Trillium rhomboideum'' {{small|Michx.}} |url=http://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:328449-2 |work=Plants of the World Online |publisher=Royal Botanic Gardens, Kew |access-date=2021-11-02 |archive-date=2021-11-05 |archive-url=https://web.archive.org/web/20211105101736/http://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:328449-2 |url-status=live }}</ref>
<ref name="POWO:542553-1">{{cite web |title=''Trillium grandiflorum'' {{small|(Michx.) Salisb.}} |url=http://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:542553-1 |website=Plants of the World Online |publisher=[[Royal Botanic Gardens, Kew]] |access-date=4 November 2021 |archive-date=10 November 2021 |archive-url=https://web.archive.org/web/20211110071909/http://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:542553-1 |url-status=live }}</ref>
<ref name="USDA">{{PLANTS|id=TRGR4|taxon=Trillium grandiflorum|access-date=15 December 2015}}</ref>
<ref name="VASCAN">{{cite web |title=''Trillium grandiflorum'' {{small|(Michx.) Salisb.}} |url=https://data.canadensys.net/vascan/taxon/6658 |publisher=Canadensys |access-date=23 March 2023}}</ref>
}}

==Bibliography==
* {{cite book |last1=Case |first1=Frederick W. |last2=Case |first2=Roberta B. |year=1997 |title=Trilliums |location=Portland, Oregon |publisher=Timber Press |isbn=978-0-88192-374-2 |url-access=registration |url=https://archive.org/details/trilliums00case }}
* {{cite book |last1=Gledhill |first1=David |title=The Names of Plants |year=2008 |edition=4th |publisher=Cambridge University Press |url=https://books.google.com/books?id=NJ6PyhVuecwC |isbn=978-0-521-86645-3}}
* {{cite book |last=Lamoureux |first=Gisèle |year=2002 |title=Flore Printanière |location=Saint-Henri-de-Lévis, Quebec |publisher=Fleurbec |isbn=978-2-920174-15-3 |pages=48; 429–449|language=fr }}
* {{cite thesis |last=Lampley |first=Jayne A. |date=2021 |title=A systematic and biogeographic study of ''Trillium'' (Melanthiaceae) |type=PhD |publisher=University of Tennessee |url=https://trace.tennessee.edu/utk_graddiss/7031 |access-date=10 February 2022}}
* {{cite journal |last1=Lampley |first1=Jayne A. |last2=Gereau |first2=Roy |last3=Floden |first3=Aaron |last4=Schilling |first4=Edward E. |title=A revised subgeneric classification of ''Trillium'' (Parideae, Melanthiaceae) |journal=Phytotaxa |date=2022-07-05 |volume=552 |issue=5 |pages=278–286 |doi=10.11646/phytotaxa.552.5.1|s2cid=250368253 |doi-access=free }}

==External links==
{{Commons category}}
* [http://bison.usgs.ornl.gov/api/scientificName/Trillium%20grandiflorum/arguments/itis Biodiversity Information Serving Our Nation (BISON) occurrence data and maps for ''Trillium grandiflorum'']{{dead link|date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}
* {{inaturalist taxon |55402 |Large White Trillium}}
* {{cite web |last1=Candeias |first1=Matt |title=When Trillium Flowers Go Green |url=https://www.indefenseofplants.com/blog/2021/5/28/when-trillium-flowers-go-green |website=In Defense of Plants |access-date=10 November 2021 |date=June 1, 2021}}
* {{cite web |title=Flower-Visiting Insects of Large-Flowered Trillium |url=http://www.illinoiswildflowers.info/flower_insects/plants/lf_trillium.htm |website=Illinois Wildflowers |access-date=15 December 2021}}

{{Floral Emblems of Canada}}
{{US state flowers}}
{{Taxonbar|from=Q1548077}}

[[Category:Trillium|grandiflorum]]
[[Category:Ephemeral plants]]
[[Category:Flora of Canada]]
[[Category:Flora of the Eastern United States]]
[[Category:Flora of the United States]]
[[Category:Flora of the Appalachian Mountains]]
[[Category:Plants described in 1803]]
[[Category:Taxa named by Richard Anthony Salisbury]]
[[Category:Provincial symbols of Ontario]]
[[Category:Symbols of Ohio]]