Hemp has been grown for 12,000 years for fiber and food. It has been effectively prohibited in the United States since the 1950s because Randolph Hearst owned vast acres of forest that he used to make paper and he didn't like competition.
George Washington and Thomas Jefferson both grew hemp. Ben Franklin owned a mill that made hemp paper. Jefferson drafted the Declaration of Independence on hemp paper.
Because of its importance for sails (the word "canvass" comes from "cannabis") and rope for ships, hemp was a required crop in the American colonies.
Hemp can yield 3-8 dry tons of fiber per acre, 4 times what an average forest yields and it is an annual harvest. Trees take 20 years to become ready to harvest. Processing hemp into paper uses fewer chemicals than wood and the paper made from hemp does not yellow with age. Hemp paper recycles easier than wood pulp paper.