Front Range winters can take a toll on your trees and shrubs, and this past season has been particularly tough on them. Many people are noticing that their evergreens look “burned” and have brown needles. This is called winter desiccation (“winterburn”). If you recall, back in November, we had a day of near 70 degrees, and that same night it plummeted to below zero. This is a drastic temperature change, and something soft-needled and broadleaf evergreens simply cannot handle.
Generally speaking, these brown needles are dead, and will not come back. The tree or shrub may or may not, and this spring it will become a waiting game for all of us. It will require patience to see how everything comes out of dormancy and pruning efforts should wait until a determination is made as to the extent of the damage.
Leaf bearing trees, and roses may also be affected, and there is also the possibility that spring-flowering trees will exhibit damage and not produce the flowers we are accustomed to enjoying.
Here is a good article on the situation: http://csuhort.blogspot.com/2014/12/frozen-2-tree-edition.html
Another article to use for reference is: http://bit.ly/1L0Q2D5