The climate is changing in many temperate forests with the amount of forest area dominated by sugar maple experiencing an insulating snowpack expected to shrink between 49 and 95% compared to 1951-2005 values. A reduced snowpack and increased depth and duration of soil frost can injure fine roots, which are essential for plant water uptake. Water uptake is a crucial component of ecosystem functioning because this process strongly impacts other biological processes, such as primary productivity and nutrient uptake. We evaluated the effects of changing winter climate, including snow and soil frost dynamics, by measuring sap flow rates in the Soil Freezing Study plots at the Hubbard Brook Experimental Forest.