In a narrow wooded valley just inside the Fukushima evacuation zone, a cold mountain dusk is falling over the terraced plots where Genkatsu Kanno grew rice and vegetables for most of his life. The idle fields are illuminated by lights from his house, where several men bend intently over a low wooden table as they pore over satellite photographs and contour maps. “So where did you say the drinking water spring is?” asks Tatsuaki Kobayashi, a restoration ecologist at Chiba University, as he studies a print showing the valley’s forest-and-field patchwork. Kanno extends a thick brown finger, carefully tracing the path of the water from its upslope source down to the house that he is permitted to visit but no longer live in. Akihiko Kondoh, a hydrologist also at Chiba University, says the spring could be contaminated with radioactive cesium if heavy rains flood the area.1 Kanno, 65, says he’s thinking of digging a well so he can live and farm in the valley again one day. Top: Kawauchi, Fukushima Prefecture 2012; Bottom: Chernobyl, Ukraine 2006 On this evening a year and eight months after multiple explosions at the Fukushima Daiichi Nuclear Power Plant, the men are grappling head-on with one of the most widespread and complex environmental health threats Japan has ever faced: Before fallout released by the March 2011 explosions arrived in the cities that line Fukushima Prefecture’s central corridor, it drifted northwest over the small, cultivated valleys, meandering creeks, and post-and-beam farmhouses of the Abukuma Mountains.2 The region’s residents depended on this land for clean water, wild foods, and firewood. Forests and wooded neighborhoods like Kanno’s are at the center of the dilemma. The questions Kanno and his neighbors are asking about their forests and their families’ health resurface again and again at local, prefectural, and national meetings. They aren’t alone. Around the world, government officials and scientists have been struggling for decades to manage nuclear-contaminated forests in ways that minimize radiation exposures for human populations. Although significant environmental contamination from accidents at reactors and military facilities dates back to the 1950s,3 the dilemma of how to manage contaminated forests emerged most dramatically and most publically after a reactor at the V.I. Lenin Nuclear Power Plant near Chernobyl blew up on 26 April 1986. The accident released a massive amount of radioactive contamination through the western Soviet Union and across northern Europe.4,5 It fell most heavily near the power plant, in a region covered in forests and fields. The problems the contaminants brought would not disappear quickly. Although radiation from iodine-131 falls by half in just eight days, the half-life of cesium-137 is 30 years; for plutonium-239 it’s 24,100 years. Soviet officials took immediate steps to limit the health impacts of the contamination by removing the region’s residents. Since the 1991 breakup of the Soviet Union, the land has been managed as a protective buffer where trees and other plants help stabilize the contamination within a mostly uninhabited area. This strategy has become the world’s principal model for handling severe radioactive contamination at the landscape level. For it to work, however, governments must permanently ban people from large areas or accept that those who remain will be exposed to more radiation than the International Commission for Radiological Protection recommends for the general population.6 In contrast, Japan’s current recovery plan revolves around removing contamination from the landscape to allow residents to move back home. In this context, contaminated forests represent not a buffer but a threat to public health. Still, the question of whether forests can—or should—be cleaned up remains extremely controversial. Two years after the Fukushima disaster, Japan’s government has not yet decided whether it will follow the Chernobyl template for forest management or instead try to create a new model for postnuclear environmental remediation.