Duabanga (Duabanga moluccana Bl.) is one of the exellent commodities for Nusa Tenggara Barat (NTB). Wood product of this species for construction, building material, and furniture. The species has developed for people forest in Lombok Island. However, the quantitative information about its stand growth is lack. The research was aimed at obtaining the information of stand growth as well as growth and yield models of sustainable stand management. The research was conducted at the Rarung Research Forest which is located in the Rinjani Forest Group, Central Lombok District. Observation was done every year from 2003 to 2006 on permanent measurement plots of 70 m x 70 m in the 1996 duabanga stand and on circle plots of 625 m² in the 1997 stand. The result indicated that the values of Mean Annual Increment (MAI) of diameter, height, and volume for the ten years old 1996 stand were 3.29 cm year^-1 , 1.97 m year ^-1, and 25.02 m³ ha^-1 year ^-1 respectively. For the nine years old 1997 stand, the value of MAI of diameter, height, and volume were 3.77 cm year ^-1, 2.16 m year^-1, and 34.41 m³ha^-1year^-1 respectively. The estimation model of stand diameter (D) and height (H) based on stand age (X) can be formulated as follows: 1) In the 1996 stand, D (cm) = 1.6622 X 1.3075 and H (m) = 1.3159 X 1.1913 , 2) In the 1997 stand, D (cm) = 5.6751 X 0.8150 and H (m) = 2.1623 X 1.0102 , and 3) In the 1996 and 1997 stand, D (cm) = 7.2015 X 0.6627 dan H (m) = 2.6550 X 0.8834

The size quality of produced timber are greatly affected by the suitability of planting density and the practice of thinning. Density effects on stand growth and development were evaluated in spacing trial or merkus pine (pinus merkussi Jungh. Et de Vriese), and these data were used to establish a stand density management diagram (SDMD). Growth performance in terms of diameter at breast (D), total height (Ht) and mortality rate monitored for 32 years when trees were 5-36 years old. Mortality and D growth were positively density related, but H growth was not affected by density. During the measurement period, tree density decreased from 7779 to 679 trees/ha for the closest spacing and from 943 to 514 trees/ha for the widest spacing. Result suggested that optimal harvesting was at about 30 years of age if no thinning occurs. The SDMD was established to predict the course of stand development in merkus pine. The simulation of stand growth under 2 x 3 m spacing and thinning options was demonstrated in a a SDMD, and suggested reasonable flexibility for practical application. We recommend using this SDMD as tool to reexamine the thinning regime for enhancing forest productivity and wood utilization