"Chill with climate change: are warmer winters a problem for plants?", Al Kovaleski, Plant Resilience Lab, University of Wisconsin
The survival of woody perennial plants in temperate and boreal environments depends on proper responses to low temperatures. In North America, winters are warming faster than other seasons. As low temperatures limit survival of plants, are warmer winters improving conditions for plants in the future?
In many species, leaves and flowers for the following growing season are packed into buds during summer and fall. These buds must avoid breaking and growing during unseasonal warm periods in fall and winter but must respond to similar warm temperatures in spring. Dormancy is what controls growth through yet unknown mechanisms that require exposure to cold (chilling) prior to allowing buds to be responsive to warm temperatures (forcing). Once dormancy is established, buds must also attain cold hardiness to be able to survive low temperatures in the middle of the winter. Both dormancy and cold hardiness must be lost in a coordinated manner in spring for plants to break bud and make use of the growing season.
In the Plant Resilience Lab, we study the coordination between these two winter physiology traits at many scales, using natural and experimental temperature gradients, how this can drive adaptation to both cold and warm environments, and in species that span forestry, ornamental, and fruit crops.