The Stand Data tab is used to specify the current stand attributes and initial volume for pines and hardwoods. Current stand attributes include age, trees/acre, base site index or observed dominant height, and basal area (ft2/acre) if known.
The base age for site index is 25 for pine plantations and 50 for hardwood stands. If base site index is not known for pine stands, then it is estimated iteratively from observed dominant height, silvicultural treatments, and genetic improvement.
Hardwood competition in pine stands should be entered as the percentage of total stand basal area in hardwoods. When the Hardwoods species button on the Stand Info tab is selected, the Hdwd Trees/acre textbox is enabled and the Percent hdwd basal area textbox changes to accept Hdwd basal area (ft2/acre).
If initial pine product weights are known, an interpolation procedure can be used to match with predicted volume after 10 years. Checking the Match initial volume checkbox allows initial weight by product to be entered. The difference between observed and predicted initial weight is calculated for each product and divided by 10 to determine the annual adjustment. The difference between initial observed and predicted volume is removed after 10 years. A thinning treatment during the 10-year period discontinues the interpolation process unless volume matching after thinning is disabled on the Options tab.
Initial hardwood product volumes in pine stands and initial pine product volumes in hardwood stands grown are grown by applying a growth rate obtained from empirical yield functions for pine-hardwood and upland hardwood stands, respectively.
