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Author's personal copy286 Trees (2012) 26:283–290Fig. 2 Photographs of the tree rings of the eight tree species in Mt. Gutian subtropical forest of China. a Pinus massoniana, b Schima superba,c Cunninghamia lanceolata, d Quercus serrata, e Daphniphyllum oldhami, f Castanopsis eyrei, g Castanopsis fargesii, h Castanopsis tibetanagrowth) over the lifetime of the tree. Schima had a complexgrowth pattern. The young trees showed high, lineargrowth rates, whereas the older trees showed fast earlygrowth, followed by a distinct reduction in growth rate andthen a later increase in growth. The dashed lines in Fig. 5indicate constant diameter growth of 1 mm per year, whichis clearly exceeded by most individuals of Pinus andCunninghamia.Radial growth dynamics among speciesFig. 3 Ring-width chronologies of the four species in Mt. Gutiansubtropical forest of China40–105 years for Quercus. This wide range of age for agiven tree size derives from the high variability of individualgrowth trajectories within the species (Fig. 5). MostPinus and Cunninghamia showed fast early growth withdecreasing growth rates in larger trees. In contrast, Quercusgrowth trajectories were relatively linear (i.e., constantSpecies differed strongly in mean age–size relations(Fig. 6). Trees around 5 cm in diameter had comparablemean ages for Cunninghamia, Schima and Pinus trees, butthe ages differed strongly among species at larger diameter.For instance, mean ages at 20 cm in diameter varied from55 years in Cunninghamia trees to more than 85 years forSchima and Pinus trees. The average age–size relations ofSchima and Pinus trees were very similar. Quercus treestended to have slow and constant growth over their entirelife span and showed the highest average ages at anydiameter. Cunninghamia owned the highest average radialgrowth rate among the four species.The four species under study showed different patternsin growth rates (Fig. 7). Schima had the highest mediangrowth rates of the four species, followed by123177