A large tree in full leaf can "lift" well over a ton of water a day from the soil and carry it along an elaborate system of pipelines to every leaf. Most of this water is returned to the air through a process called transpiration. On that same day, the same tree may transpire several hundred gallons of water into the air, cooling as much air as would six window-unit air conditioners.
Wind is estimated to cause about 30% of annual soil erosion, on agricultural cropland. Wind erosion is primarily due to tilled fields lying exposed for long periods between growing seasons. Forest crops are rotated over decades rather than annually, so wind is not a major erosive factor for forests.
A typical tree uses nearly a pound-and-a-half of carbon dioxide and gives off more that a pound of oxygen to grow one pound of wood. An acre of trees might grow 4,000 pounds of wood a year, use 5,880 pounds of carbon dioxide and give off 4,280 pounds of oxygen in the process. One mature tree absorbs approximately 13 pounds of carbon dioxide a year. For every ton of wood a forest grows, it removes 1.47 tons of carbon dioxide and replaces it with 1.07 tons of oxygen.
An average, large, healthy tree could have about 2,000 leaves. During 60 years of its life, such a tree could grow and shed approximately 3,600 pounds of leaves. Those leaves return about 70 percent of the nutrients to the soil.
Three well-placed mature trees around a house can cut air-conditioning costs by 10-50 percent, while trees and other landscaping can increase property value by 5-10 percent.
Clearcutting is the only effective means to regenerate forest types adapted to catastrophic disturbance and are intolerant of shade.
Fall color timing is based mostly on photoperiod (actually the increasing number of night-time hours). Color intensity and persistence is influenced by forest health conditions, frosts, other weather factors.
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