Linda Halley and I stand in the middle of a seemingly empty, sunny field under an impossibly clear sky. She bends over and touches her fingertips to the soil, raking them gently over the top, exposing slightly blacker, wetter soil underneath the grayish first layer. "I don't see any – Oh! There's one. Do you see that?" she asks. "That's the beginning of a weed," Halley explains. Now I see it. She's turned up a tiny matchstick of white, barely noticeable, and easily dismissed as a piece of dried grass. It's the sliver of the root or maybe a stem. Weeds: competition for nutrients, water, and sunlight. Weeds: enemy of the crop and therefore enemy of the farmer. As the manager of the Minnesotan organic farm, Gardens of Eagan, Halley can't use herbicides to rid herself of these pesky plants.