Since tree species are controlled by climate; do they affect the climate?

I love reversed logical questions, yes i'm sure it can help but to what degree? I think our problem is way too big for just planting trees! even if in large numbers. We are using far too much energy at an alarming rate and in process we produce far too much greenhouse emissions than the life on earth can cope. We have to reduce our emissions, we have to stop this way of life and find another cleaner and friendlier option. A green environment does not mean in any way reducing our privileges or our technological gains, it's the exact opposite.