Warming climate could speed forest regrowth in eastern U.S. Duke Today, April 16, 2018. Warming climate could speed the natural regrowth of forests on undeveloped or abandoned land in the eastern United States, according to a new study. Previous research has shown that the succession from field to forest can happen decades sooner in the southeastern U.S. than in the Northeast. But it wasn’t obvious why. A new study points to temperature as the major factor influencing the pace of reforestation.