Given a random empty block in nether biome after destroying Nether Sprout

When destroying nether sprout, upon picking it up I am given a weird looking block with no HUD name and only a blank space for an inventory name. It shows as nothing in my hand and cannot be placed back down. When mining blocks with the glitched nether sprout, the surrounding environment is not affected e.g. mining a block next to a lava pool, the lava does not fill the empty space.