Project Results

About This Project

In the Willamette Valley, there are mysterious stands of aspen far separated from any other wild aspens, whose origin is completely unknown. We believe these trees were brought here by cataclysmic floods originating in Montana ≈15,000 years ago. Through in-depth genetic comparison of these “lost aspens" with others throughout the west, we can determine their origin. This could be the first study showing dispersal of any species by massive floods.

Ask the Scientists

What is the context of this research?

During the late Pleistocene epoch, an ice sheet stretched across Canada with lobes reaching into WA and MT, damming the Clark Fork River in western MT. This created a massive lake known as Glacial Lake Missoula, and 15,000 years ago, the dam broke. This caused a series of catastrophic floods with discharges more than ten times the combined flow of all rivers on earth, scarring the landscape forever. Some of the waters back-eddied into the Willamette Valley, depositing massive boulders, fertile soils, and potentially living trees that persist today! The location, structure, and proximity of these aspens to flood deposits suggests that they were not planted, but originated somewhere in the flood's path. Sequences in their DNA can be analyzed in-depth to indicate their true origin.

What is the significance of this project?

The Missoula floods were a major force shaping the Pacific Northwest ecoregion. They are well known in native American folklore, and literally sculpted the valleys and soils in a major part of this region. Understanding how they have also shaped the distribution of forest trees will add to our knowledge and love of this amazing part of the planet. No previous research has shown how biblical-style floods can reshape biological distributions, so this research would allow us to better understand the natural history of our region, as well as dynamics that shape biological communities worldwide.

What are the goals of the project?

We will genetically fingerprint the lost aspens and the potentially related populations of aspens in our region, then publish the results. We will:1. Finish collection of all 100 samples2. Extract DNA from all samples3. Make "DNA libraries' and check their quality4. Sequence those libraries with a method called GBS, producing millions of data points per tree for an in depth genetic fingerprint5. Analyze genetic fingerprints with computer programs to determine the evolutionary relationships of aspens in the region, and thus their likely origin6. Publicize results to all contributors and offer seedlings of flood aspens to major donors (of over $100) if our hypothesis is correct7. Publish results in newspapers and a conservation journal