Half-Sib Progeny Test and Superior Cunninghamia lanceolata Family Selection

The indexes including tree height, DBH and standing volume of 72 halfsib progeny families of Cunninghamia lanceolata were measured for 1yr, 2yr, 3yr, 4yr and 25yr old trees that were sampled from Xishan Forest Farm in Rong’an County. The results showed that there were significant or extremely significant differences in these index values among most of the families. Most of the growth traits were extremely significantly and positively correlated with the ages. The growth traits of the most families were stable and highly consistent along the age increment. However, there was great change in these growth indexes between the juvenile and mature stages of some families, showing the instability along the age increment. According to the growth index values of 25yr old mature stage, 27 halfsib progeny families including Liu241, Liu244, Liu220, Shankou10, Guangyun171 with highly integrated gain were screened out, whose highest gains in tree height, DBH and volume was 26.29%, 62.68% and 110.42% respectively.