Translocation of cesium in the branches of Japanese cedar (Cryptomeria japonica) and Konara oak (Quercus serrata)

133CsCl solution was applied to the foliage of Japanese cedar (Cryptomeria japonica) and Konara oak (Quercus serrata) under field conditions to investigate whether radiocesium could be translocated from the foliage to other parts through senescence of foliage, and whether this differs between tree species. 133Cs was translocated to nearby foliage in both species, whereas translocation to the base of the branches was observed in Konara oak, but not in Japanese cedar. These results suggest that the translocation of radiocesium towards woody branches might be more prominent in Konara oak than in Japanese cedar through senescence of foliage.