In this paper, we present the longest tree-ring chronology of oriental beech from Artvin, identify the most important climate factors affecting radial growth, and compare our results with the oriental beech chronology from Belgrad Forest. | Research Article Turk J Agric For 36 (2012) 501-509 © TÜBİTAK doi: The effect of temperature and precipitation on the intra-annual radial growth of Fagus orientalis Lipsky in Artvin, Turkey Nesibe KÖSE*, Hüseyin Tuncay GÜNER Forest Botany Department, Faculty of Forestry, İstanbul University, 34473 Bahçeköy, İstanbul - TURKEY Received: ● Accepted: Abstract: In this paper, we present the longest tree-ring chronology of oriental beech from Artvin, identify the most important climate factors affecting radial growth, and compare our results with the oriental beech chronology from Belgrad Forest. Stem disks were taken from 10 living oriental beech trees, and earlywood and latewood bands were measured separately in addition to ring width. The longest (442-year-long) chronology of earlywood, latewood, and total ring width for oriental beech were built from Artvin, Turkey. All chronologies (earlywood, latewood, and total ring width) were found to be highly sensitive to climate with mean sensitivity values of , , and , respectively. Pearson correlation coefficients were used to identify relationships between tree radial growth and climate. The results showed that the most distinctive effect of temperature on tree-ring growth occurred with maximum temperature. High mean and minimum temperatures in the period of March to July (especially in May) resulted in growth early in the growing season and wide earlywood, latewood, and total ring formation. Different from Belgrad Forest chronology, precipitation was a limiting factor on tree growth, but only in June. High temperatures had a positive effect during the period of March to July and did not cause a drought problem. Key words: Climate-growth relationship, earlywood, latewood, oriental beech, tree-ring Introduction The genus Fagus L. is distributed in temperate areas of the northern hemisphere, East Asia, Europe and West Asia, and North America (Fang and .