One thing: you will not have any of the blocks or trees from extrabiomes but it will still look cool, trust me.
Okay, what you want to do is download schematics of trees. There are many ways to find tree schems on sites such as planetminecraft. Go into your worldpainter until you can get custom stuff on your brush. Click the add extra layer and it will pull up a little box that you can add your schems to and use them in a brush.
And there you have it some very nice forests with many different looking trees.
It's not perfect but, it's a good stand in.
Private Mod Note
Rollback Post to RevisionRollBack
Dokucraft Fantasy by Prophecy_Wrecker http://www.minecraft...0#entry22202253
This pack is a conglomeration of many textures by the Dokucraft community compiled and edited by Prophecy_Wrecker. The pack has a dark, fantasy feel to it and it comes with its own soundpack!
Being that the modding community in Minecraft is so large would it be possible for anyone in which is relatively experienced with code create a plug-in for World Painter that would allow support for mods such as Biomes O' Plenty and Extra Biomes XL.