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Radioactive carbon dioxide was utilized to trace carbohydrate translocation in blue grama, sideoats grama, and switchgrass. Tagged tillers retained 77% of their fixed carbon following a 24-hour translocation period. The roots were the strongest sink of assimilate, receiving 76.2% of the total 14C translocated. The pre-elongated and elongated tiller fractions received 16.3% and 7.5% of the 14C translocated, respectively. Major differences among the grasses became evident upon examination of relative total activity (RTA) ratios in elongated/pre-elongated tillers and root/shoot fractions. Switchgrass produced many more elongated tillers and had the highest elongated/pre-elongated RTA ratio. Blue grama had the greatest weight of pre-elongated tillers, a strong above-ground sink, and therefore had the lowest root/ shoot RTA ratio. Sideoats grama had RTA ratios similar to those of blue grama.