The large drone zoomed low over a field of corn at Sandborn Farms in Portland, Mich., spraying fertilizer with strategic precision. Some of the poorest-growing sections of the farm are no longer planted with crops at all, aimed instead at supporting pollinators and other wildlife. Precision agriculture — farming that harnesses technologies like drones, satellite imagery and artificial intelligence to improve yields, save money and reduce environmental harm — is already transforming the way the world grows food. But the innovations on display at Sandborn Farms take it a step further, into what’s known as precision conservation. It’s a twist that elevates ecological benefits as a central goal instead of just a happy byproduct.