Another study seemed especially applicable to Apple. In 2009, researchers at California State University Northridge studied carbon sequestration on the university’s 350-acre campus. Students inventoried all 3,900 trees by type and size. Using data from the Center for Urban Forest Research, a branch of the U.S. Forest Service, they estimated the amount each tree was likely to sequester. The average was 88 pounds per tree per year. (By contrast, the average American is responsible for emitting about 44,000 pounds of carbon annually.) Then they compared total sequestration to the amount of carbon emitted by campus sources. (Those sources included the production of electricity to power campus buildings—but not transportation to and from campus.) The result: The trees sequestered less than one percent of the amount of carbon released during the same period. Put another way, the amount of carbon sequestered, at a school with 41,000 students, equaled the carbon output of eight average Americans.
http://www.archdaily.com/875782/how-sustainable-is-apple-parks-tree-covered-landscape-really/
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