Pining for the Ancient Bristlecones

The Ancient Bristlecone Pine Forest is home to the oldest trees in the world, Bristlecone Pines.  Some of these living trees exceed 4000 years of age and exhibit spectacular growth forms of twisted and beautifully colored wood. The best place to see bristlecone pines is in Schulman Grove in Inyo National Forest in the White Mountains of eastern California.

In the White Mountains, the ancient bristlecone pines seem to show a preference for growing on the white, rocky soil broken down from dolomite, a type of limestone created under the warm, shallow, inland sea that once covered this area. The bristlecone pines don't actually "prefer" this soil type. Other plant species have a very difficult time growing in it and the bristlecones, because they have adapted to this high alkalinity, have a chance to get established and grow in a near competition-free environment.

There are many trees in the bristlecone pine forest of the White Mountains that exceed 4000 years of age, and are still growing! Bristlecone pine wood that has fallen to the ground can remain intact for thousands of years in the cold, dry climate of the White Mountains. Using a cross-dating technique that overlaps tree-ring patterns of living trees with the still intact patterns of dead wood, scientists have assembled a continuous tree-ring chronology extending nearly 10,000 years. This bristlecone pine chronology, developed here in the White Mountains by University of Arizona researchers and Dr. Henry Michael of the University of Pennsylvania is the longest in the world and provides an unequaled look into past climatic and environmental conditions.  It is so precise that it has been used to recalibrate radiocarbon dating techniques and make them more accurate, thus helping us more accurately date events and fossils that have nothing to do with the bristlecone pines.

The features of bristlecone pines that help them grow so old are also the features that help dead bristlecone pine wood survive the elements:  because of the harsh environment, the trees grow very slowly; their wood is extremely dense and resinous.  This makes them resistant to disease when alive and erosion when dead.  Here is a good example of the bristlecone pine:

We wanted to visited the Ancient Bristlecone Pine Forest in the White Mountains near Bishop, where we are staying, and learned that the Schulman Grove, the best local example of bristlecone pines, is located within an hour's drive of our campground. We stopped at the local National Forest Visitor Center and were told that, while the Schulman Grove Visitor Center was presently closed due to snow, we were free to drive up and hike through the bristlecone pines.  However, we would have to park the Jeep early and hike in because of snow.  This was acceptable, so we made our plans and did some further research on the bristlecone pines.

Edmund Schulman, a dendrochronologist at the University of Arizona, was the one who discovered that the bristlecone pines are the oldest trees in the world. Schulman spent much of his career studying old trees. He found 1500-year-old limber pines in Idaho, and dated many of the 3000+ year old giant sequoias. A ranger in the Inyo Mountain area knew of very old trees in the White Mountains and invited Schulman to visit. Schulman first sampled the more vigorous bristlecone pines located on a north-facing slope but could find none older than about 1500 years. One day he ventured up the opposite, south-facing slope where smaller, less vigorous-appearing trees were growing and took a core from a terribly decrepit looking pine. This tree proved to be much older.  Three years later, in 1956, he returned to help locate the sites most likely to have the oldest trees. Ironically, these are the poorest growing sites, where the very slow growth yields dense, resinous wood. He found an entire grove with many trees over 4000 years old, which he named the Methuselah Grove.

Soon after Schulman's death at an early age in 1958, the Forest Service designated much of the ridge of the White Mountains as the Ancient Bristlecone Pine Forest and granted it considerable protection. The area where Schulman did most of his research on bristlecone pines is now called the Schulman Grove. The Forest Service built what is now known as the Schulman Grove Visitor Center where he made his first discovery, and has constructed a beautiful 4-mile trail starting at the Schulman Grove Visitor Center which winds through a variety of bristlecone habitats, including the Methuselah Grove.

Our drive up to Schulman Grove wound upward through the foothills of the White Mountains from Big Pine, California.  The road, while paved, is narrow and winding and presents spectacular scenery as an added bonus.  A small section of the road is one-lane, hemmed on each side by lichen-dressed rocks:

After a drive that was an adventure in itself, rising above the snowline to a point where, finally, our path was blocked by a huge drift of snow covering the road, we climbed out, donned our winter hiking gear, and hiked the final 1.7 miles in to the Visitor Center, which sits above 10,000 feet!  This is the view that presented itself to us as we hiked in:

Eventually, we reached a sign that told us we were nearing our goal.  David points the way:

Not another 15 minutes and we arrived at the Visitor Center.  Kathy poses at the entrance sign:

By the time we reached Schulman Grove, it was lunchtime, and we were hungry, so we threw off our packs and sat under the eaves of the Visitor Center porch to eat our sandwiches.  As we ate, we decided we would do a 1-mile hike through Schulman Grove itself.  Below, Kathy stands at the beginning of the trail:

Our hike took us on a 300-foot climb up one side of a large hill and down the other side.  Periodically, we found information signs or dramatic viewpoints.  All along the trail were beautiful examples of bristlecone pines and their near relatives, the limber pines.  Here, Kathy stands at one of the viewpoints:

We decided that the fellow below was the most dramatic example we could find of the bristlecone pines. 

The sign next to the tree shown above explains that its roots are exposed because 2-3 feet of soil has been eroded by wind from around the tree.  This exposure of the tree's roots is what caused its death.  Scientists are not sure why bristlecone pines die (disease doesn't seem to be a cause), but, aside from climate change or extreme changes in the local environment, the only likely cause is eventual erosion of soil causing root exposure, which scientists think makes the tree vulnerable to disease or prevents the tree from taking in moisture or nourishment.

Up close, the wood of a bristlecone pine's trunk and roots are spectacularly colored, reminding us of colored layers of sandstone that twist and curl.  Here, Kathy examines the beautiful patterns of the wood:

After we reached the high point of the hill, our path swung around to the western flank and we worked our way down the slope, getting a view south, looking back up the road we had hiked in to Schulman Grove.  We could see that clouds were building and that some weather was coming in.  We though it was prudent to start heading back to the Jeep, out there somewhere over 2 miles away.

We reached our Jeep just before the clouds crept up the mountains and reached us.  When they did, as we started our drive down the steep, curving road, we were pelted with hail, sleet, snow and rain.  It seemed the hail returned every time the road traveled along the western face of the mountains.  Our progress down the mountains was careful and slow, but it gave us a chance to enjoy the beautiful and dramatic scenery of this little-known corner of California.

Tomorrow, we hope to do a real snowshoe for the first time in a few years.  Stay tuned to see if it comes to pass.