The tree above is a mature Jeffrey pine we passed descending Grouse Mountain on our trail run Sunday. In a clearing, the crown of this tree has become so large and asymmetric its trunk has become bowed. (Brett is standing by the tree to give an idea of its size.)

Jeffrey pines can vary in stature from the stunted and wind-blown tree photographed by Ansel Adams in Yosemite to this champion big tree in Trinity National Forest that is over 200 ft. tall.

Depending on the rigors of its environment, Jeffrey pines and other conifers may stop gaining height, but often continue to increase in girth, expand their crowns, or grow near or along the ground.

Trees may be shaped through the actions of wind, fire, pollution, rain, snow, ice, flowing water, lightning, hail, sunshine, UV radiation, soil creep, animals, insects, plants, fungi, geology, and more. We were wondering what caused the contorted shape of this tree near Sheep Camp.

Here are some additional examples of trees that have been shaped by their environment:

• Windswept Jeffrey pine on Dawson Peak
• Wally Waldron limber pine near the summit of Mt. Baden-Powell
• Sierra juniper on the North Backbone Trail on Pine Mountain
• Sugar pine on Kratka Ridge near Mt. Williamson
• Lodgepole pine on the North Backbone Trail
• Jeffrey pine struck by lightning, near Mt. Hawkins
• Southern foxtail pine near Cirque Peak (Sierra Nevada)