Recently I downloaded an old map with an epic forest of mega trees. But, the map was so old it crashed a few times and chunks went missing. So I used MCedit to salvage the remaining piece of intact forest. Then I placed multiple plots of that mega forest schematic onto an AMPLIFIED map. Enjoy!
Credit to the original map i created a huge forest schematic from: http://www.minecraftworldmap.com/worlds/LYgIM