J. FOR. SCI., 63, 2017 (8): 339–343 339 JOURNAL OF FOREST SCIENCE, 63, 2017 (8): 339–343 doi: 10.17221/23/2017-JFS Selection of promising black locust (Robinia pseudoacacia L.) cultivars in Hungary Károly RÉDEI 1,2 , Imre CSIHA 3 , János RÁSÓ 3 , Zsolt KESERŰ 3 * 1 Hungarian Horticultural Propagation Material Non-profit Ltd., Budapest, Hungary 2 Department of Plantation Forestry, Forest Research Institute, National Agricultural Research and Innovation Centre (NARIC), Sárvár, Hungary 3 Department of Plantation Forestry, Forest Research Institute, National Agricultural Research and Innovation Centre (NARIC), Püspökladány, Hungary *Corresponding author: keseru.zsolt@erti.naik.hu Abstract Rédei K., Csiha I., Rásó J., Keserű Z. (2017): Selection of promising black locust (Robinia pseudoacacia L.) cultivars in Hungary. J. For. Sci., 63: 339–343. In Hungary the black locust ( Robinia pseudoacacia Linnaeus) is one of the most important exotic stand-forming tree species growing mostly under unfavourable ecological conditions. Considering the climate change effects its importance is increasing also in many other countries. As a result of a selection programme several black locust cultivars have been improved for setting up cultivar trials. In the paper four black locust cultivars were evaluated in Central Hungary under arid hydrological and brown forest soil conditions. Significant differences ( P < 5%) were found in height, DBH, mean tree volume and average stem form value (SFV). At the age of 35 years the cultivar “ R. p. Jászkiséri ” appeared to be the most promising one for yield production and “ R. p. Zalai ” and “R. p. Nyírségi ” for SFV. Keywords: climate change; clonal approach; growth; yield Black locust (Robinia pseudoacacia Linnaeus) is a species native to North America that has a long tradition of uses as an ornamental tree, forest tree, street tree, and is also favoured by beekeepers. Te tree is naturalised in many parts of the world in- cluding Asia, Africa and several countries in Eu- rope. Black locust is an early successional species readily colonising open grounds, but not regener- ating in the shade, usually outcompeted by longer living hardwoods in the course of succession. Since the introduction of black locust into Hun- gary this tree species has been closely associated with agriculture, and its wood could be utilized for many agricultural and domestic purposes. Af- ter World War II its importance changed because large-scale farms had lower demand for wood and the timber industry was not willing to buy black lo- cust wood. It was necessary to improve the quality of fnal products of black locust forests to meet the demands of consumers. Terefore, new cultivars had to be produced by selection techniques and had to be introduced into the practical forestry use (Keresztesi 1988). Te strategy aimed to improve the quality of black locust stands, which were considered to be sepa- rate provenances. In the best black locust stands tree groups of shipmast stem form, then plus trees were selected by B. Keresztesi and his colleagues (Keresztesi 1988). Te ofspring of these select- ed trees were propagated in a vegetative way (root cuttings) and were grouped together into variet- ies. Tus, varieties are mostly composed of several clones, but there are also some one-clone varieties. Propagation of cultivars was frst planned by seedlings, but the seed orchards produced small quantities of seed. So it was necessary to develop