Like others in the so-called good-food movement, [Will] Allen, who is 60, asserts that our industrial food system is depleting soil, poisoning water, gobbling fossil fuels and stuffing us with bad calories. Like others, he advocates eating locally grown food. But to Allen, local doesn't mean a rolling pasture or even a suburban garden: it means 14 greenhouses crammed onto two acres in a working-class neighborhood on Milwaukee's northwest side, less than half a mile from the city's largest public-housing project. And this is why Allen is so fond of his worms. When you're producing a quarter of a million dollars' worth of food in such a small space, soil fertility is everything. Without microbe- and nutrient-rich worm castings (poop, that is), Allen's Growing Power farm couldn't provide healthful food to 10,000 urbanites - through his on-farm retail store, in schools and restaurants, at farmers' markets and in low-cost market baskets delivered to neighborhood pickup points. He couldn't employ scores of people, some from the nearby housing project; continually train farmers in intensive polyculture; or convert millions of pounds of food waste into a version of black gold. With seeds planted at quadruple density and nearly every inch of space maximized to generate exceptional bounty, Growing Power is an agricultural Mumbai, a supercity of upward-thrusting tendrils and duct-taped infrastructure.