Volunteers for Assisted Migration & Rewilding
of Torreya taxifolia
Torreya taxifolia, America's most endangered conifer tree, is on the brink of extinction in its "native range" in the Florida panhandle. As explained in the Rewilding section of this website, some Torreya Guardians have concluded that T. tax would be native to northern Florida only in the peak cold times of a glacial advance, such as occurred some 15 to 20 thousand years ago. Since then, as interglacial warming has occurred, native range for T. tax should have been moving north, well beyond the "pocket refuge" of Florida's Apalachicola River Bluffs and northward into the southern Appalachians and Cumberland Plateau.
Because T. tax specimens that were planted 60 years ago at the Biltmore Gardens in Asheville NC are thriving (and continue to produce, on their own, healthy recruitments), it can be argued that the southern Appalachians should be the destination for assisted migration of T. tax. This argument for action is based entirely on a strong biodiversity ethic: plant T. tax where it will thrive.
Land stewards near Waynesville, North Carolina, stepped forward
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| CAUTIONARY NOTE TO POTENTIAL PARTICIPANTS IN THE ASSISTED MIGRATION OF THIS ENDANGERED TREE: Just in case genus Torreya is able to cross-pollinate between its distinct species that have been geographically isolated from one another in the wild for millions of years, please do not plant any Torreya taxifolia seeds or seedlings in proximity to either the California species (T. californica) or any of the Asian species (the latter of which are widely available in commercial nurseries). Please keep them miles apart. Genus Torreya is wind-pollinated. And even though this species is ostensibly dioecious (an individual produces either male or female reproductive structures), there have been reports of individual Torreya trees violating this rule. So caution is advised.
As well, if you own property west of the Mississippi, do not attempt to grow Florida Torreya there. We wish to keep America's eastern species of Torreya well isolated from wild stands of the native (and threatened) western species — which may ultimately need to migrate northward into Oregon in future centuries. (There is paleoecolgical evidence of Torreya genus in Washington state.)
This cautionary note applies, as well, to any growers who would like to assist with the other conifer "left behind" in the Appalachicola peak-glacial refuge of the Florida panhandle: Florida yew (Taxus floridana). Do not plant this endangered tree near other yew species, if you wish its seed to be useful for conservation purposes. |
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The Fossil Record
The biodiversity argument for assisted migration can be supplemented by an understanding drawn from deep time: T. tax was found in previous eras in what is now North Carolina.
Torreya is a member of the ancient gymnosperm family Taxaceae, whose ancestors were evolutionarily distinct from other conifers by the Jurassic, nearly 200 million years ago. Because Torreya pollen is indistinguishable from the pollen of yews (Taxus), bald cypress (Taxodium), and cypress (Cupressus), known fossil occurrences of this genus are limited to macrofossils (seeds, leaves, and secondary wood), and these are sparse. There are no known Cenozoic fossils of Torreya in eastern North America. The most recent macrofossils identified as the genus Torreya in eastern North America are upper Cretaceous, and these were unearthed in North Carolina and Georgia.
Because Torreya pollen is indistinguishable from that of some other conifers, only macrofossils (leaves, wood, seeds) provide evidence for how geographic range has shifted through millions of years.
Because worldwide climate during the Cretaceous was much warmer and far less seasonal than that of today, it is not surprising that Torreya macrofossils of Cretaceous age have also turned up along the Yukon River of Alaska. In western North America, there is Cenozoic fossil evidence of genus Torreya in the John Day region of Oregon (lower Eocene) and variously in California (Oligocene and late Pleistocene). Today, the genus is highly disjunct. Torreya californica survives as a rare tree, locally abundant in a score of isolated populations within the coastal mountains of central and northern California and on the west slope of the Sierras. It favors moist canyons and mid-slope streamsides, growing beneath a canopy of taller conifers and deciduous trees. Torreya nucifera is found in mountain habitats of Japan and Korea, and three other species of genus Torreya inhabit mountainous regions of China.
Recruiting Private Land-Owners
As explained in the Saving Torreya section of this website, a lot of effort is being expended to attempt (1) to preserve the few trees that remain in the wild in Florida, (2) to clone genotypes for safe-guarding in "potted orchards" in various botanical gardens, and (3) to replant progeny from the potted guardians in or near Florida native habitat. These three actions are taking place under the auspices of a legally sanctioned recovery plan for this endangered species, as administered by the U.S. Fish & Wildlife Service.
The official recovery plan is not, however, the only approach available. So long as private seed stock is the source, there is nothing that prevents any landowner from planting Torreya taxifolia on his or her private property.
A no-budget, self-organizing, completely volunteer, and paperwork-free recovery "plan" is hereby proposed on this website.
