Its hard to establish a Economy system with all those AutoFarms. We have plenty Plugins wich disables MobFarms/Traps. But only one Plugin wich tries to eliminate thos Cacti Farms. (Wich still allows Player to break Cacti via Pistons and Receive a drop, wich doesnt really Help on my Server) I like to disable Drops for Cacti and Reeds/SugarCane completly if not destroyed directly by a Player. Hope there is someone who can build a lightweight Plugin for that, maybe with a Configurable list wich Blocks doesnt yield a drop.
