Forest inventory costs with bitterlich sampling method (PNA) and cross cluster sampling (CC) in Pinus taeda L. stands.

This study was carried out in three different stands of Pinus taeda L., non-thinned and aged 10, 9 and 7 years. The stands had 2.000 trees per hectare and are located in Parana State. The aim was to evaluate the costs of inventories using Bitterlich Sampling and the sampling method with Cross Cluster to analyze the behavior of accuracies and relative efficiencies for estimation of the variables: average diameter at breast height, number of trees, basal area and total volume per hectare. For this study, sample units of 40 were taken for the PNA method and 10 units for the CC method, which is composed of four subunits and the randomized design block was used. It was concluded that for the variable number of trees per ha the use of the plot sampling with Cross Cluster is indicated, since the cost to obtain this variable is lower. For the variables diameter (cm), basal area per ha (m2) and total volume per ha (m3) the use of the Bitterlich sampling method (PNA) is indicated, since the cost is lower with these variables.