Is Global Warming going to hurt our forests?

Hello as you may know my name is cbgbyo65 and today I will be talking about how Global Warming might be hurting our forest's.The trees that most seem to be dying are Pine, Firs, and Hemlock's.There are many possiple reason's why this could be happening like o-zone related air pollution, long-term effect's of fire suppression, and normal forest dymatic.This has been happening most often in California with the highest death rate, and with most of those tree's being Pine.There is still not an exact reason for this event yet.I've got this information from cnn/technology.com ,but in my opinion I would say it is from the o-zone pollution and focus on that.