Pseudotrillium rivale

There have been several large wildfires within the distribution of this species. One in particular, the Biscuit fire of 2002 which straddled the California and Oregon border, covered the entire extent of this species' range (LaLande 2019). High timber mortality was reported in the aftermath of this fire. Although the region in question has historically been fire-dependent, recent fire suppression regimes have lead to a build-up of dead timber, which results in much hotter, more severe burns. Though the impacts of forest fire on this species are not well studied or understood, it is likely that long term disturbance to habitat caused by forest fire has adverse impacts, such as habitat invasion by non-native plants. More research is needed. 

Other threats to this species are not well documented but could include predation by elk (Cervus canadensis), competition with invasive plants, and logging. A related species, Trillium ovatum, has undergone substantial population decreases as a result of logging practices within the Siskiyou Mountains (Jules 1998). However, Brook Wakerobin’s preference for serpentine soils, which are less productive for timber extraction purposes (Kruckeberg 1992), may protect this species from logging.

Though not specifically protected in either California or Oregon, the majority of the species' habitat falls within the Rouge River-Siskiyou National Forest  (IUCN and UNEP-WCMC 2019). Within this range, logging is still permitted and the level of protection afforded by presence in a semi-protected area is questionable. Greater levels of protection are afforded in small portions of the species’ range which occur in the Smith River National Wild and Scenic River, and the Kalmiopsis, Wild Rouge, and Grassy Knob Wilderness Areas. Additional population surveys and monitoring are needed to better understand the population trend of this relatively restricted species. The species is not known to be included in any seed bank accessions (Center for Plant Conservation 2019). However, it is known to be cultivated in the horticultural trade, and ex situ collections of the species are held at two botanic garden sites (BGCI 2019).