If by plant life you mean trees, there are more acres of forest land today than at the time of the Pilgrims. Also the increases in CO2 in the atmosphere stimulate forest growth.

But this thread is bout oil at $85 a barrel. That is pure supply and demand with a little speculation thrown in. Increase the supply and the price goes down. We can't do much on the demand side without irreparable damage to the economies of the Western world. We have plenty of good ole crude oil just waiting for us to tap it. Certain segments of society block that for various reasons. The best answer for electricity generation is nuclear. But you can't put that in a car or airplane...yet...