I-Stem kunye ne-leaf winnowing machine ifanelekile kwimifuno eyomileyo, amaqabunga eti, ukutya okomileyo ukususwa komzimba wangaphandle, usebenzisa ukhetho oluthile lomxhuzulane, ukunikezelwa kobungakanani, ukulawulwa komoya kunye nezinye iindlela.Inokususa umzimba wangaphandle onzima kwimveliso egqityiweyo, njengale: ilitye, isanti, isinyithi;Umzimba wangaphandle okhanyayo, onje: iphepha, iinwele, i-sawdust, iplastiki, umqhaphu wesilika.