We’ve uncovered an issue with blaze rods only within the Equestria world as much as we know. Mob dropped blaze rods are not craft-able into any item, i.e blaze powder or brewing stand. We did however stop the problem from generating more of these problem rods. So you may go forth and harvest once again. But anything harvested before Oct 15th, 2016, are subject to this sort of corruption, and will infect entire stacks if one bad rod gets in a stack. You will notice this when you are unable to craft the rods into anything, they may appear with the crafted result for a moment but then disappear soon after.
Moderators/Staff will help you by exchanging your rods for new ones. If you find you have a bad rod, try to isolate it and present it to a moderator or admin. As this kind of rod even denies that of admin perms and it is something we very much encourage you to bring in for replacement.