Pocket-sized guide to identifying native trees of the Rockies and Great Basin, in the U.S. and Canada, from the plains to the alpine zone. Like all the plant guides in the Finders series, this book uses a key format that leads you through a series of choices to identify the plant by its leaves, needles, and other features. Explains life zones in the Rockies. Heavily illustrated with line drawings and range maps.
Rocky Mountain Tree Distribution Climate limits where trees can grow. The very things people like about the Rocky Mountain climate--cool summers and deep snow at high altitudes, year-round dry sunshine in the low altitudes--are hard on trees. The Rockies have abundant water and warmth, but not in the same places. Trees here must adapt to extreme temperatures, intense sunlight, and drying winds.
Each tree's range has an upper limit, the altitude above which it's too cold for the tree to grow, and a lower limit, below which it's too dry.
Some trees are adapted to hot, dry foothills: A three-inch ponderosa pine seedling may have roots two feet long. It can take soil surface temperatures of 180 F (82 C), but a heavy frost can kill it.
Other trees can survive short summers and bitter winters: The new needles of subalpine fir resist frost, and its branches shed heavy snow. But its roots are shallow and could not survive the dry heat of the foothills.
The next pages describe five LIFE ZONES found at different altitudes in the Rocky Mountains. Some trees grow in several zones, but if you know what zone you're in you can usually tell what trees you'll find.