suggested that the original seed disperser of Torreya might have been a now-extinct large tortoise. In the Winter 2004/2005 issue of Wild Earth magazine, an article by Barlow and Paul S. Martin titled "Bring Torreya taxifolia North — Now" offered another possible cause of dispersal problems as the glaciers retreated: extirpation of local squirrels by newly arrived Paleo-Indians inhabiting the riverside habitat and possibly also setting fires destructive of the species. Barlow's hypothesis later shifted to an intrinsic topographical barrier: perhaps "the large-seed of Torreya (which is sometimes capable of floating for several days) easily caught a fast and obstacle-free river ride southward from the Appalachian Mountains by way of the Chattahoochee River at the onset of cooling during the Pliocene or Pleistocene. But there was no river-flow way to return north during any of the interglacial warmings." Extinction Threats T. taxifolia became one of the first federally listed endangered plant species in the United States in 1984. The IUCN has listed the species as critically endangered since 1998. It is considered "the rarest conifer in North America." The Center for Plant Conservation describes Florida torreya as "one of the rarest conifers in the world," reporting that in the mid-Twentieth Century it suffered a catastrophic decline, as all reproductive age trees died. Approximately 0.3% of the original population remains, mostly as resprouting stems. The continuing threats are "changes in hydrology, forest structure, heavy browsing by deer, loss of reproduction capability, as well as dieback from fungal disease." The dieback was alarming not only for its speed and severity. Prior to its decline, "T. taxifolia was estimated to be the seventh most abundant tree species within the Apalachicola Bluffs region." In its most recent (2020) update to the Florida torreya recovery plan, the United States Fish and Wildlife Service concluded that the naturally occurring population was continuing to decrease, with little to no reproduction observed and no recruitment in its wild habitat along ravine slopes on the eastern bank of the Apalachicola River. The remaining trees were still impacted by "disease, herbivory, and deer rub, along with other confounding factors." The agency reported that the ongoing decline of torreya numbers and health was exacerbated in 2018 when the entire native range of the species took a direct hit from the Category 5 Hurricane Michael. The agency reported an estimated 80–90% loss of canopy tree cover, causing direct kills of some torreya