The following Participating Institutions are custodians for this species in the CPC National Collection:
Cincinnati Zoo & Botanical Garden
The conservation of Trillium reliquum is fully sponsored.
Linda G. Chafin contributed to this Plant Profile.
Distribution & Occurrence
- South Carolina
Mature, moist hardwood forests with deep, loamy soil in rich ravines and on stream terraces over calcium-rich bedrock such as amphibolite or limestone.
|Alabama: Eleven populations are known, most with thousands of plants, and 3 with fewer than 200 plants.
Georgia: About 40 populations are known
South Carolina: Seven populations, all of which are under intense urbanization pressure
Conservation, Ecology & Research
Trillium reliquum is largely self-incompatible and is cross-pollinated by a variety of insects; inbreeding is infrequent (Gonzales and Hamrick 2005). The flowers usually have a dark reddish-brown color and a fetid odor, both of which attract flies which typically lay their eggs in decaying organic material or fungi. The flowers produce no nectar, rewarding their insect visitors only with pollen (NatureServe 2008). Blow-flies (family Calliphoridae) and several other species of small flies in a number of different families, as well as beetles, such as rove bettles (Staphylinidae) have been observed on relict trillium flowers (Folkerts 1987, NatureServe 2008). Typically, Trillium plants may well be more than 10 years old before flowering and fruiting (Ohara 1989) and may live for several decades. As with other species in this genus, the seeds of relict trillium are myrmecochorous, i.e. they bear a small lipid- and protein-rich structure, an elaiosome, which attracts ants. Ants collect the seeds and carry them back to their nests where they feed the elaiosome to their larvae. After the larvae eat the elaiosomes, the ants carry the Trillium seeds to a waste disposal area where dead ants and ant feces create a nutrient-rich seedbed. Gonzales and Hamrick (2005) also observed yellow jackets (Vespula vulgaris) foraging inside mature fruits, suggesting that these insects may also act as seed dispersers.
Trillium reliquum is vulnerable to competition with rapidly spreading invasive species such as Japanese honeysuckle (Lonicera japonica) and kudzu (Pueraria lobata) (Heckel 2004). It is also heavily browsed by white-tailed deer (Odocoileus virginianus) which are increasing in numbers throughout the range of relict trillium (Thompson 2004).
clearcutting and logging
invasion of habitat by exotic pest plants such as Japanese honeysuckle (Lonicera japonica) and kudzu (Pueraria lobata)
Gonzales and Hamrick (2007) assessed gene diversity and determined that there are unusually high levels of genetic polymorphism in Trillium reliquum as well as incongruously low levels of genetic diversity (when compared with the common Trillium cuneatum). These findings suggest that there is little gene flow among extant T. reliquum populations, and that rarity and population isolationis of ancient origins, rather than due to recent[habitat] fragmentation. This conclusion that Trillium reliquum as a species is composed of several ancient, genetically separate populations has implications for conservation. In order to preserve the full range of the species genetic potential, a large number of populations spread across the species range need to be protected.
Heckel (2004) examined the impacts of Japanese honeysuckle (Lonicera japonica) and kudzu (Pueraria lobata) on Trillium reliquum population dynamics and reproduction as well as on the community structure of trillium habitat. He concluded that these invasive vines were associated with altered community structure and reduced seed set, seed size, and population density. Projections of trillium populations over time suggest that trillium populations that occur with kudzu will be extirpated in 15 years. Management efforts should focus on controlling invsive plant species, monitoring reproductive and non-reproductive transition rates of T. reliquum, and improving reproduction.
Thompson (2004) studied the impacts of white-tailed deer (Odocoileus virginianus) and Japanese honeysuckle (Lonicera japonica) on Trillium reliquum in central Georgia He found that white-tailed deer herbivory decreased fruit production and increased dormancy in T. reliquum and that removal of Japanese honeysuckle results in significant increases in population size. Conservation efforts for T. reliquum should focus on long-term deer population management, the control of invasive plant species, and conservation of subadult and reproductive individuals.
Current management recommendations include: protect hardwood slope forests from human activity, including logging, clearing, and prescribed fire; eradicate exotic pest plants, especially Japanese honeysuckle and kudzu; reduce the size of deer populations (Chafin 2007, NatureServe 2008).
determine population size and stage-class distribution for all populations
study biotic and abiotic features of the habitats that support relict trillium, including pollinators and seed dispersers, relationship with competitors and herbivores, and soil and light requirements.
establishment of long-term demographic studies in permanent plots
determine effects of disturbance from human activities such logging, use of herbicides, etc.
determine the size of the area and other requirements needed for the extablishment of self-sustaining populations
techniques and protocols for seed collection, germination, propagation, and transplantation be developed for relict trillium
plants be maintained in cultivation in botanical gardens
long-term seed storage be undertaken
plants be made available for sale in retail outlets to reduce the threat of poaching
Flora of North America. 2003. Flora of North America, Volume 26, Magnoliophyta: Liliidae: Liliales and Orchidales. New York. Oxford University Press. 752p.