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As part of an effort to integrate straw and grain harvesting operations, an investigation was undertaken of the cutting properties of straw to aid the development of novel header systems for combines. Results can also be extended to other industrial operations involving straw handling and size reduction. Average cutting force and energy for stems were measured using a custom designed double sickle knife mechanism. Treatments involved single and multiple stems. Cutting properties were determined at regular intervals along the stem, including both internode and node sections up to the third stem internode, with detailed force and energy profiles developed in the immediate vicinity of the nodes. Cutting energy per stem was found to decrease as the number of stems cut simultaneously increased, partly as a result of the sensitivity of cutting force to location relative to the stem nodes, and partly due to the failure mode when multiple stems are cut. Results were compared against field measurements of operating sickle cutters used for on-combine stubble cutting. Theoretical power required for cutting the stems amounts to only 5 -15% of total cutter power due to other factors relating to increased machine friction and cutting force. Results for rice straw are compared with data from other forage crops.