When you try to use Bone Meal on a planted tree branch in a crowded area (eg directly next to another tree where it's impossible to grow) causes the Bone Meal to deplete by 1 each time you try to use it (when it fails to grow the tree).
When you try to use Bone Meal on a planted tree branch in a crowded area (eg directly next to another tree where it's impossible to grow) causes the Bone Meal to deplete by 1 each time you try to use it (when it fails to grow the tree).
Doesn't it work that way in regular MC? I think this is by design.
From the wiki, emphasis mine:
Saplings: When applied, one bone meal is consumed and the sapling may grow instantly into a tree, provided it has enough space, light, and luck.
http://www.minecraftwiki.net/wiki/Bone_Meal