14CO2 was supplied to leaves, and movement of labelled carbon to other parts of the plant was assessed. Young growing leaves utilized assimilated carbon for their own growth and did not export carbon to the rest of the plant, while fully expanded leaves exported much of their photosynthate, both to root and to young leaves. Translocation from a particular leaf was to the two or three younger leaves on the same side of the plant, and to a sector of root below the source leaf. Specific distribution to growing leaves could be modified by partial defoliation. There was no movement of material to leaves which had emerged before the source leaf. Part of the carbon entering a leaf by assimilation (and, for young leaves, by translocation) was incorporated into insoluble material, especially in young leaves. Some of the carbon entering a developing root was permanently stored as sucrose, although much also entered insoluble material. Loss from the leaf of carbon fixed during a short period of photosynthesis was rapid at first but continued at a decreasing rate for several days. Some carbon fixed into the insoluble fraction was translocated from the leaf later, during senescence. Sucrose was the main material translocated immediately after photosynthesis.