It's a pity that our school system has failed so many people by not teaching them some basics of economics, which is that the supply of trees is elastic and can increase with demand/price, and will decrease with decreased demand/price.

Not using trees will only incentivize people to re-allocate land that was used for the cultivation of trees to the cultivation of something else that is higher demand, and thus profitable.

The only way that not using paper will save trees is if we stopped all forms of cultivation/farming.