A study the juvenil phase persistence in clones of Citrus expressed by the thron presence was made. The eight clones observed belong to the basic collection of nucellar matrix plants of the Agronomic Institute of Campinas. The torn control was done in new plants obtained from buds from various matrix plant positions, that were 24 and 18 years old. It was verified juvenil tissue presence in all new plants, with variable intensity according the tree position from where the buds was obtained. We found among clones, variation in the thorn size and number probably influenced by the bud source of the original seedling, and the prunning intensity done in the matrix plants.