Back in February, Pia described the excitement of a film crew’s visit to the lab, and now we have the results to share with you! This past Thursday, Sally and many members of the lab were featured on The Nature of Things in an episode entitled Dreams of the Future. It’s available to watch online if you’re in Canada. While I’m not encouraging you to skip ahead, the Aitken lab segment starts about 35-40 minutes in.
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.
Old whitebark pine (Pinus albicaulis) on McGee Pass Trail by Miguel Vieira
My current research is on lodgepole pine, but I originally considered working on whitebark pine. Whitebark pine is an iconic species of sub-alpine ecosystems in western North American mountains. It can survive a millennium in harsh, cold environments, but climate change, pests, and disease are now threatening it with extinction.
Sierra McLane planting whitebark in an experimental plot. Photo by Sally Aitken and used with permission of Sierra McLane.
I came across this paper by Raffa, Powell, and Townsend that made me think whitebark pine just can’t seem to catch a break! Between disease, fire suppression, climate, and now beetles, it’s in real trouble. It turns out the trees have no natural resistance beetles to speak of. They do seem to do better in mixed stands, but that’s only because the beetles seem to like lodgepole better.
However, there’s still hope for whitebark pine. One of the things that could change its prospects would be assisted migration. A changing climate doesn’t just render current range unsuitable; it transforms locations outside the current range into potential habitat. Aitken lab alum Sierra McLane tested whether this might be possible a few years ago. She planted whitebark pine seeds in experimental plots north of the current range and found that whitebark was able to establish north of its current range. No one has decided to move whitebark pine, but Sierra’s work gives us insight into how to do it if we ever do make that decision.
There’s a paper coming out soon in Environmental Applications discussing the ethics of moving whitebark pine. They conclude:
We are not arguing here for anything as strong as a duty to relocate the whitebark pine. However, we do consider that there are good reasons to do so, and few very strong ethical objections. Our claim is that if rust-resistant strains of whitebark pine can be clearly identified, depending on the outcome of economic and feasibility studies, and consultation at particular sites, there are likely to be places where relocation of whitebark pine is ethically desirable.
McLane SC, Aitken SN: Whitebark pine (Pinus albicaulis) assisted migration potential: Testing establishment north of the species range. Ecological Applications 2011, 22:142–153.
Palmer, C. and B. M. H. Larson. 2014. Should we move the whitebark pine? Assisted migration, ethics, and global environmental change. Environmental Values (online first). [pdf]
Raffa, K. F., Powell, E. N. & Townsend, P. a. Temperature-driven range expansion of an irruptive insect heightened by weakly coevolved plant defenses. Proceedings of the National Academy of Sciences (2012). doi:10.1073/pnas.1216666110
Last year, Aitken lab alum Jill Hamilton published a paper in the American Journal of Botany, Genetic and morphological structure of a spruce hybrid (Picea sitchensis × P. glauca) zone along a climatic gradient. I interviewed Jill about her paper and got the story behind the research last August. Listen to the interview:
Jill is currently a postdoctoral fellow with Dr. Janice Cook at the University of Alberta where she is part of large genomics projects on both white spruce and lodgepole/jack pine. She will be joining Johanna Schmitt’s lab at UC Davis this summer.
Outi Savolainen, Martin Lascoux and Juha Merilä lay it out in a recent paper in Nature Reviews Genetics.
Savolainen, O., Lascoux, M., & Merilä, J. (2013). Ecological genomics of local adaptation. Nature Reviews Genetics, 14(11), 807–20. doi:10.1038/nrg3522
