Selection of LargeSized Cunninghamia lanceolata Superior Trees and Variation Analysis on the Major Economic Traits

Taking DBH as selection index, 38 superior Cunninghamia lanceolata individuals (DBH≥26cm) were selected from 23yr old progeny plantation inside the primary seed orchard. The realizedgain of DBH of all the superior individuals was all over 56%. Further analysis revealed that the tested economic traits including height, DBH, standing volume, bark ratio (BR), wood basic density (DEN) and wood hygroscopicity (WH) varied greatly among the superior trees, and the variation coefficient was over 10%. It was also found that the height, DBH, volume, and WH were positively correlated to each other significantly or extremely significantly (significance <0.05 or 0.01) among the superior trees, while there were significant or extremely significant negative correlations between BR and DBH, standing volume, between DEN and WH and each growth index. According to the classification results of the superior trees in VB (volume without bark) and DEN, 17 individuals were identified to have a higher level of VB than that of the mean value of the superior trees population (PM), and the DEN value of superior S14, S18, S22, S25 trees displayed a relatively high level than that of PM.