Based on measurements of the diameter at breast height and height of 1031 trees taken on ten study plots in Slovenia, a comparison was made between the calculations of living standing tree volumes and growing stock by one parametric volume functions (adapted uniform French tariffs) with two parametric volume functions and stem taper equations. It was also checked the difference between the calculation of the growing stock of trees calculated using one parametric volume functions and the internationally harmonised COST Action E43 definition. The findings show that these methods are statistically different from each other, with the two parametric volume functions giving on average 9% higher estimates of volumes and growing stock in comparison with one parametric volume functions and the stem taper equations 3% higher. Estimates of the growing stock by the harmonised method were 12% lower. Comparing the estimates of conifer and broadleaved growing stock according to the national definition (one parametric volume functions) and the harmonized method, it was found that conifer growing stock is 9% higher and broadleaved growing stock is 14% higher.
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