Whitebark pines are majestic trees with a whitish, often wind-curled trunk that grow up high in the Rocky and Sierra Mountains, in the Western US. They’re icons of Yellowstone National Park, where they provide high-calorie seeds for many animals, including grizzly bears that eat the seeds before hibernating. Some whitebark pines manage to live for a thousand years, but many of them are now dying.
Greg Breining writing in Ensia on assisted gene flow and assisted migration:
During the last two springs, contract planters for The Nature Conservancy have spread out through the pine, spruce and aspen forest of northeastern Minnesota. Wielding steel hoedads, they have planted almost 110,000 tree seedlings on public land.
What’s noteworthy about planting trees in a forest? Usually foresters plant seedlings grown from seeds harvested nearby, on the assumption that local genotypes are best suited to local conditions. But these TNC workers were planting red and bur oak (which are uncommon in northern Minnesota) from seed sources more than 200 miles to the southwest, and white pine from as far away as the Lower Peninsula of Michigan, 400 miles to the southeast.
TNC is anticipating a day soon — within the lifespan of a tree — when a changing climate may make the forest unsuitable for some tree species and varieties that now live there.
Aitken, S., & Whitlock, M. (2013). Assisted gene flow to facilitate local adaptation to climate change. Annual Review of Ecology, Evolution, and Systematics, (September), 1–22. doi:10.1146/annurev-ecolsys-110512-135747