Bristlecone and Limber Pine Upslope (IMAGE) University of California - Davis Caption Dead bristlecone pine trees stand on a steep slope in the western Great Basin of California's White Mountains. They are increasingly being joined by limber pine trees in a slow motion game of 'leapfrog' upslope. Credit Brian Smithers/UC Davis Usage Restrictions Provide credit License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.