Credit: Victor O. Leshyk
Results from the SPRUCE experiment in northern Minnesota show how experimental warming treatments in a boreal peatland forest resulted in earlier spring green-up by trees and shrubs. A severe spring frost caused extensive damage to the warmed foliage that had lost its winter hardiness. In the control treatments, the vegetation was not damaged by the frost despite temperatures dropping to about 5 degrees Fahrenheit (-15 degrees Celsius).