Desiccation is a big concern going into the spring of 2013. Desiccation occurs when the requirements for water in trees exceeds the available moisture that is in the soil for the roots to uptake.
Here in central Iowa, we have been seeing dead spruce, arborvitae, white pines, and the like. These species continue to have requirements for water throughout much of the winter season. Desiccation also can affect evergreen species such as boxwood and rhododendron.