Trillium recurvatum

The species is at high risk for predation and is browsed more frequently than other herbaceous species (Anderson 1994). Population declines in co-occurring closely related species may also be occurring as a result of  White-tailed Deer (Odocoileus virginianus) overabundance within its range (Augustine and Frelich 1998, Knight et al. 2009, Russell et al. 2001). In related species, White-tailed Deer also disperse seeds leading to an antagonistic relationship between seed dispersal and population fecundity (Vellend et al. 2006). The capacity for clonal reproduction may alleviate the impact of White-tailed Deer herbivory, though the precise relationship between herbivory levels and reproductive mechanism is unclear. An exclusion study conducted in Illinois demonstrated 38% population increases for Prairie Trillium following three years of deer exclusion (Frankland and Nelson 2003). However, exclusion responses cannot be interpreted as indicative of long-term population trends and additional research is needed. Forest management practices may also negatively impact some subpopulations (NatureServe 2019). Habitat loss associated with clearance for agriculture is noted to have caused forest fragmentation which may be compounded by pollen limitation within remaining subpopulations (Sawyer 2010).

The species is listed as Threatened in Michigan (USDA, NRCS 2019). Though not protected in much of its range, the species incidentally occurs in several protected areas (IUCN and UNEP-WCMC 2019).