Timber Cruising with Point Sampling and Product Estimator

A sampling procedure for volume estimation is presented,in which volume is computed as the product of average basal area per hectare and average volume-basal-arearatio(R).The basal area estimate is obtained by point sampling,and R is estimated by subsampling point/sampled trees.Expression for the variance of the product estimator is also given.Simulated tests show that for the same degree of precision,using this sampling method is over that of the double sampling for ratio estimator.