Excerpts from Jim Conrad's
Naturalist Newsletter

from the October 10, 2004 Newsletter issued from the Sierra Nevada foothills somewhat east of Placerville, California, USA
PINE ZONES

A local lumberman explained the situation with our local pines. He said:

"Down in the canyon, and getting as high as almost here, there are Digger Pines. Here we have Ponderosa Pines. Right above the Ponderosas, the Sugar Pines come in with those big cones."

That's a striking thing about being here in the Sierra Nevada foothills. If you pay attention, the vegetation zones reflecting elevation changes are obvious, and it's surprising how little elevation change is needed to alter the forest's composition.

Of course the zones grade into one another, and there's some overlap of the species' elevation preferences. At our latitude, drought-tolerant, wispy-looking Digger Pines occur between 500-3000 feet in elevation. Our handsome Ponderosas grow from 3000-6000 feet, but the giant-coned Sugar Pines overlap them, preferring 3500- 6500. So, right here we're in a narrow band that's OK for Ponderosas, but too low for Sugars.

Precipitation and forest luxuriance reaches its peak above us at 5000-6000 feet. Higher up, yet other pine species appear, adapted for colder, drier conditions. Jeffrey Pine grows at 6000-8500 and Western White Pine at 6500-9500 feet. Finally, in the Alpine region, scraggly, slow-growing Lodgepole Pine appears between 6000-10,000 feet, and even higher-growing Whitebark Pine survives at 9500-11,000 feet.

Other tree species are mingled with the pines, but the pines tell a nice story all by themselves.