An effective separation is the basis for the growing of high quality potatoes, carrots, onions and other crop on stony and cloddy fields. The GRIMME destoners of the CS-series are developed for this purpose. The CS series is designed for high performance, best separating quality and the highest economy. Various combinations of stars and main webs give the right solution for the individual grower. The patented RotaPower-shaft increases the sieving output about 25 % compared to traditional systems. The rotor shaft crumbles the compacted soil and prepares it for an increased sieving. Wear and tear of the following star rollers and main webs is significantly reduced.