Accuracy testing of Wolf von Wulfing stand table in estimating teak stand volume

Abstract

The Wolf von Wulfing (WvW) stand table made in 1932 is commonly used to estimate the volume of teak stands at a certain class of site quality (bonita) and age. A state forest enterprise (Perum Perhutani) usually uses the WvW table to estimate the volume of stands at the end of the cutting cycle or in other words used to determine the annual allowable cut (AAC). The accuracy level of estimated stand volume using WvW table still needs to be tested. This study aims to test the accuracy of the Wolf von Wulfing stand table in estimating the volume of teak stands (Tectona grandis), using measurement results data on teak stands in the Forest Management Unit (FMU) of Ciamis (West Java) and Randublatung (Central Java). We conducted an analysis by comparing the stand volume using the WvW table with the stand volume obtained using the local volume table (TVL) that already available in each study location. Data analysis was performed using simple linear regression: Y = (30+|31X; X = Volume WvW; Y = Volume TVL. Regression analysis results showed that the relationship between Volume WvW (X) and Volume TVL (Y), expressed through the equation of Y = -2.83 + 0.88X, with the value of R2 adj=0.94. Hypothesis testing results on the value of (30 and (31, states that the value of (30=0 and (31^1, so that it can be concluded that the alleged results with the WvW table are overestimating. Alleged overestimate results can cause overcutting so that forest management is not sustainable.