This document describes improvements to a cigarette-making machine tobacco feed. It aims to more efficiently handle tobacco winnowed from shredded tobacco fed into cigarette machines. Specifically, it provides a stem box to collect undesirable stem particles from the winnowing process. It then automatically shreds the collected stem particles into a size suitable for incorporation into cigarettes using a grinding mechanism located within the stem box. This avoids the need for additional manual processing and handling of the winnowed tobacco.