In vitro growth of Quercus robur L. buds taken from 1-7 month old seedlings or adult plant material was studied. The following were investigated for their effects on the establishment of explants and subsequent subcul~res: original position and lignification of the primary explant, conditioning and ageing of source plants, incorporation of N 6 benzyladenine (BA) and activated charcoal in the medium.For bud break the best results were obtained with explants from herbaceous twigs in all tested media. For shoot growth the results depended on the medium used. Medium containing activated charcoal produced episodic growth, leaf organogenesis was reduced, spontaneous rooting occurred, but subculturing from adult plant material failed. On medium containing more than 8.8/aM of BA, all the buds developed abnormally and elongation did not occur. At lower concentrations of BA (4.4/aM) shoots elongated, leaf organogenesis was increased and episodic growth tended to disappear on subcultured seedling explants. No spontaneous rooting was observed, but subculture from adult plant material was managed successfully.