Birdsong hums over the rumble of Karl Wenner’s truck as it bounces along the dusty trails that weave through his property. For almost 100 years, this farm in southern Oregon grew barley, but now, amid the sprawling fields, there lies a wetland teeming with life. Wenner installed the wetland on 70 of the farm’s 400 acres to help deal with phosphorus pollution that leaked into the adjacent Upper Klamath Lake after his land flooded each winter. With support from a team of scientists and advocates,