Later this month, the U.S. Department of Agriculture (USDA) will formally admit defeat along one front of its battle against a devastating invasive insect. Starting 14 January, the agency will no longer regulate the movement of living ash trees or wood between states. This quarantine has, for more than 10 years, formed the cornerstone of the federal government9s strategy for curbing the spread of the emerald ash borer, an iridescent green beetle that threatens to wipe out North America9s ash trees, an ecological linchpin of many forests. Instead, USDA plans to ramp up an effort to control the borer by releasing tiny wasps that parasitize and kill the beetles. The shift is controversial. Some scientists and environmental advocates agree that, after spending some $350 million over the past 2 decades to fight the ash borer, the government should redirect scarce resources to more promising strategies. But others argue the surrender is premature, and some states are vowing to maintain local controls on ash tree and wood movement. "I worry that this decision hastens the rate at which [ash] trees are threatened," says Leigh Greenwood, a forest health specialist at the Nature Conservancy. "This is one layer of protection we9re taking away."