It was stated that adventitious roots as well as shoots formed from the buds of willow cuttings contained two GA-like substances. One of them was different in roots and in shoots. The amount of Ga-like substance in roots was much higher than in shoots. The level of these substances increased very intensively in roots while in shoots rather slightly and only in the earlier stages of their growth. The results of later experiments and of others presented here shown that adventitious roots of willow cuttings are the sites of gibberellin biosynthesis. Possible explanation of existing of different gibberellins in roots and in shoots is also discussed.