When I need lots of wood I wander to my line of 64 oak trees (I plant he saplings adjacent) and hit it with my lumber axe. The only issue is if I got more than a few great oaks in the line it will instantly break my axe. (full iron axe, not the best but good enough)
It's probably easier to make the 2x2 Dark Oak or Spruce Trees. I've got four large Spruce trees planted and each harvest is 10-12 stacks of charcoal. (With Lava+Fortune3 on a Lumber Axe). Ring of Magnetism to easily collect all the stuff.
For the Axe:
Obisidan Head, Paper Binding and Plate (make sure that the binding comes before the plate), Slime Tough Rod, Gold Block + Diamond and Diamond Block + Golden Apple enhancements. That gives 7 available upgrades to start with. I used 4x Reinforced (brings it up to Reinforced 7, which lasts a decently long time), Lava, Fortune and Speed.
Then upgrade the rod to Thaumium (used for another Reinforced) and later the head to Refined Glowstone (which makes the axe indestructible). Thaumium can be gotten very early from Thaumcraft research, Refined Glowstone needs Mekanism machines and might take a while.