Summary of the problem Dirt placed with Unbreakable Wand never grows grass Pack Version 2.5.4 What is the bug? If you place down a pad of earth the usual way and add one block of grass, the grass will spread somewhat slowly to all of the dirt blocks converting the rest of the dirt to grass. If you place any of the dirt blocks with an Unbreakable Wand (4339:12), those dirt blocks never convert to grass. If you then break these wand placed blocks and put them back manually, the grass spreads to the manually placed blocks. No dirt spreading from wand placed blocks continues across logins so there is some stored serialized data that is not correct. Very probably a mod bug, might be modpack "integration" but somewhat unlikely. I did not test the Extra Utilities builder wands for similar issues. Mod & Version BetterBuildersWands-0.6.1-1.7.10r80+358ee26.jar extrautilities-1.2.12.jar Link to log file Is it repeatable? Yes. Known Fix Manually place all dirt blocks instead of using the wand, if you want them to become grass. Plausible Guess: I would guess that all dirt blocks are "tracked" somehow for possible grass spreading and that the unbreakable wand does not add them correctly to the list when it places them in the world.