Restoration Agriculture: Balancing Agriculture and the Environment

Restoration agriculture posits that agriculture and natural environments do not have to be at odds—and that imitating nature may be the most efficient way to produce perennial food crops.

Oak savanna plants
This list of species and their arrangement from taller to shorter is somewhat of a Rosetta Stone for perennial agriculture systems in North America. Evidence shows that the current species that make up the North American oak savanna have ebbed and flowed through no less than four different ice ages.
Chart courtesy Acres U.S.A.