%0 Research Notes %T On the profitability of fertilization especially in forest stands on peatland %A Hämäläinen, Jouko %D 1984 %J Suo - Mires and peat %V 35 %N 4-5 %U http://suo.fi/article/9597 %X The article presents some earlier published results (Folia Forestalia 570) on the profitability of fertilization of mature Scots pine stands growing on drained peatland in southern Finland (Tables 1, 2 and Figures 1, 2). NPK-fertilized pine stands growing on drained peatland were clearly more infertile than the PK fertilized plots, and hence the study is not concerned with alternative NPK or PK fertilization on plots of the same type. Preliminary results concerning the profitability of fertilization of mature Norway spruce stands on drained peatland are also given. According to these results, fertilization of spruce stands, which were naturally more fertile than pine stands on peatland, seems to be slightly more profitable. The profitability of single applications of fertilizer on peatlands is also compared to that of single and repeatedly fertilized stands on mineral soils (internal rate of return). Single PK-fertilization of mature spruce stands on drained peatland seems to give nearly the same profitability as single N fertilization of mature spruce stands on mineral soils. Single PK fertilized mature pine stands on peatland also attain almost the same profitability level as both spruce stands. On the other hand, a higher internal rate of return is obtained with single N fertilization of mature pine stands on mineral soils than with the other fertilization treatments described above. Repeated fertilizations begun in young or middle aged stands are not so profitable as single fertilization on mature stands.