National Geographic : 2012 Sep
3 2 1 2 3 0mi 4 0km 4 SCALE IS FOR ALL THREE INSET MAPS. Bangor Kearney Platte AREA ENLARGED M ississippi NEBRASKA MAINE RICH FLOODPLAINS The Mississippi River fertilizes a wide corridor where forests give way to corn, cotton, and soybean fields. President Lincoln's exchange of square plots for railroad track led to checkerboard logging in the West. Belts of forest straddle rivers surrounded by farms dug into the nearly treeless Midwestern prairie. Cities like Bangor, Maine, inch into postcolonial regrowth that covers 80 percent of New England. TREE FARMS In the Southeast fast-growing trees are planted as crops. Some softwoods, like pine, are harvested every 20 years. MAP: JEROME N. COOKSON, NGM STAFF; GREG FISKE, WOODS HOLE RESEARCH CENTER; THEODORE A. SICKLEY. SOURCES: NASA; U.S. FOREST SERVICE; USGS FOREST BANDS Development proceeded in stripes along the Appalachian range. Woods remain on slopes too steep for building.