Black locust (Robinia pseudoacacia L.) is the most important fast growing stand-forming tree species in Hungary. Its importance is increasing in many other countries, too. As a result of a new selection programme 13 black locust clones have been improved for setting up clones trials and seed orchard. In 2003 five of them (R.p. Bácska', Homoki', 'Szálas', Oszlopos' and Vacsi') were registered as cultivar­candidates. Tissue culture method has proved as a suitable mean of propagating superior individuals. The micropropagated plants have been growing successfully in the clone trials.