%0 Research note
%T Comparison of approaches to integrate energy wood estimation into the Finnish compartment inventory system
%A Tahvanainen, Timo
%A Kaartinen, Kalle
%A Pukkala, Timo
%A Maltamo, Matti
%D 2007
%J Silva Fennica
%V 41
%N 1
%R doi:10.14214/sf.310
%U https://silvafennica.fi/article/310
%X The harvesting of energy wood from young stands is increasing as the  demand for renewable wood fuel is growing. Energy wood consists of  stems, tree tops, branches and needles, depending on the size of the  trees and the logging method used. The current forest inventory and  planning systems used in private forests in Finland do not produce  estimates of energy wood components. In stands typical for energy wood  harvesting, a large share of energy wood consists of trees smaller than  the minimum size for pulpwood. In this study, energy wood was included  into the calculation system of compartment inventory, and a procedure  for simulating the thinning treatments in young stands was developed.  The results for six inventory alternatives and prediction of energy wood  were compared with the use of inventory material from 37 young stands  that have plenty of energy wood. The measurement of additional stand  characteristics and the use of a calibration estimation method was  tested, as well as the use of plot-level inventory data instead of stand  level data. The results showed that the measurement of the number of  trees per hectare, in addition to stand basal area and mean diameter,  improved the energy wood estimates. The additional minimum and maximum  diameters improved the precision of the estimates, but did not affect  bias. The removal estimates were more precise when plot-level data was  used, rather than stand-level data. The removal estimates were higher  with plot-level data. The results suggest that, in heterogeneous young  stands, plot by plot prediction would give more accurate removal  estimates than the calculation of a corresponding prediction at the  stand-level.