Summary:

The article analyses spatial differences in the afforestation of agricultural land in the mountain and piedmont areas of Poland. Apart from quantitative and structural changes in the area of new forest plantations, attention was paid to socio-economic determinants of the process of afforestation of agricultural land. The changes considered were those formally registered, which means that areas with a natural succession were not included. The analysis rested on the statistics collected in the Regional Data Bank and basically covered the years 2000-2006, but for private land use was made of the 1996–2006 data. The object of study was mountain and piedmont communes in the Carpathians and Sudeten. The research showed there to be a drop in the area of afforestation of agricultural land over the study period, which resulted from the diminishing area of new forest plantations on both, state-owned and private land in the two regions. This process was undoubtedly connected with the level of financial support, which was clearly evident especially in the case of private land. It was found that the financing of afforestation was a major factor in the rate of this practice. In each of the regions the changes followed a similar pattern, but differed in dynamics. Differences in the internal structure of afforestation resulted from the different agrarian structures of the regions, while spatial differences in the rate of afforestation was also an effect of socio-economic factors.