Über die produktivität der ackerund waldböden Finnlands

Agricultural soil productivity in Finland is examined from the standpoint of the classification of agricultural properties for taxation purposes, what was valid until 1968. Field areas are classified according to their natural quality and productivity, the average productivity being expressed in ‘taxable hectares’, the mean value for which is calculated for each commune. This productivity may also be calculated from the yield of oats, which may be compared with the classification used for taxation and with estimations of soil fertility. The taxation of forest areas is based on forest types. By noting the regional variations in tree productivity on soils included under the same forest type and also the distribution of forests, a ‘taxable cbm‑number of timber’ is obtained for each commune, upon which this study may be based. The taxation scales for field and forest areas differ in that the effect of climate upon productivity is taken into account in the case of forest areas, while the classification of field areas is based on soil quality. In terms of in­come, there is the further difference that forest yields are subject to variations in timber prices, while the prices of agricultural products are fixed. These discrepancies are corrected for taxation purposes by means of approved average monetary values for the actual yield from agricultural land per ‘taxable hectare’ and the ‘taxable cbm‑number of timber’. The field areas are subsequently divided into six, and the forest areas into four, productivity classes. In this way five agricultural and forestry productivity zones may be distinquished. It is shown that productivity decreases from the southwest and south towards the north. In the northernmost zone agricultural soil productivity is scarcely a fifth of that in South‑West Finland