The study deals with the preconditions for natural regeneration of the pine at the polar tree line in northern Finland and Sweden. The data has been collected in three summers from 1909 to 1911 in areas of Inari and Utsjoki in Finland and Kaaresuvanto, Jukkasjärvi und Pajala in Sweden. The yearly variation of seed production of pine is studied and compared with the age of the stand, site factors and weather conditions.
Intensity of reproduction is dependent on different preconditions for pistils and stamens and hence the total reproduction (formation of cones) can vary very much depending on the weather.
According the study, the formation of cones varies yearly and is particularly strong every three to four years. Supposedly the same model applies to whole polar tree line of the Fennoscandia. There seem to be no difference between northern and southern parts of Scandinavia when it comes to frequency of good cone years though they not always occur in the same years.The study is based on research in Germany, Austria, Switzerland, north Russia and Siberia, and Finland in years 1906-1908. The objective of the study is to find means to create forest site classes or forest types to direct practical forest management.
The article presents the classification of forests into site classes (Oxalis-Majanthemum type, Myrtillus type, Vaccinium type and Calluna type). The second part of the article represents different methods to calculate growth and yield tables for different forest site types. The conclusion of the study is that forest areas with similar vegetation and forest type can be handled in one way for forest management.