With the top of a bristlecone pine tree of the Patriarch Grove of California's White Mountains centered near Polaris, the North Star, the revolution of the earth over the course of two hours scribes the circular path of stars about Polaris. The star trails appear to be a vortex surrounding the bristlecone pine (Pinus longaeva), in the ancient bristlecone pine forest in the Inyo National Forest. The bent wood is known to geographers as krumholz, and is caused by the winds of the area over time.