Comparison of Growth Cause of Pure Plantations of Fokienia hodginsii with Cunninghamia lanceolata

Growth processes of 33 -year -old Cunninghamia lanceolata plantation and its neighboring plantation of Fokienia hodginsii with the same age and similar soil fertility were studied in Sanming, Fujian, China.The results showed that tree density, mean diameter at breast height (DBH), mean tree height and growing stock were 975 stem/hm², 21.6 cm, 21.37 m and 420.7 m³/hm², respectively, for the F.hodginsii plantation and 1 117 stem/hm²,23.3 cm, 21.89 m and 488.7m³/hm², respectively, for the Cunninghamia lanceolata plantation.The productivity of 33 -year -old F.hodginsii plantation was lower than that of Cunninghamia lanceolataplantation. F.hodginsii plantation grew slower in the juvenile period, but faster in mature period than Cunninghamia lanceolata.The total increment of tree height, DBH and stem volume of F.hodginsii were remarkably lower than those of Cunninghamia lanceolata within the first 10 years of age.The current annual increment of each index of F.hodginsii plantation accelerated gradually after 10 years old, and its current annual increments of tree height, DBH and stem volume exceeded those of Cunninghamia lanceolata plantation at 15, 18 and 19 years old respectively, and were 1.20, 1.35 and 1.50 times greater, individually, than those of Chinese fir plantation by 33 years old.