Current issue: 55(2)
Under compilation: 55(3)
The article is a congratulatory letter to professor Cajander. The author describes the work of Cajander about forest site classification and its importance to the development of forest sciences not only in Finland but worldwide.
The volume 34 of Acta Forestalia Fennica is a jubileum publication of professor Aimo Kaarlo Cajander.
Vegetation data collected from a random sample of mature forest stands representing mesic upland forest sites in Southern Finland were analysed and classified using two-way indicator species analysis (TWINSPAN). The variation of some characteristics of the tree stand and soil fertility between the produced vegetation units were analysed statistically.
Both the species list and the sample list arranged by TWINSPAN reflects the overall site fertility considerably well. The results are in agreement with the main division of mesic forest sites in the Finnish forest site type classification: vegetation units which can be assigned to the Oxalis-Myrtillus site type are clearly separated from the remaining units, and the overall site fertility indicates a statistically significant difference. The within-type variation in the vegetation composition in the Oxalis-Myrtillus site type reflects the variation in site fertility, whereas the within-type variation in the Myrtillus site type is mainly caused by the tree stand factor.
The PDF includes a summary in Finnish.
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.
The article contains three presentations given about forest type classification at the University of Tarto in Estonia. The article has an introduction, a part about the meaning of the natural classification of forest sites and up to now conducted studies on site classification. The second part presents the characteristics of plant communities and the forest types, and practical and theoretical meaning of forest types.
Classifying the forest sites is important in practical forestry, because the forest growth and forest valuation are dependent on the productivity of the soil. The classification of the sites for forest management purposes needs to result in classes that are easily distinguished in the forest. This then leads to forest management that best fits to a certain forest site.
The article is a review on methods used in Central Europe and in Finland to construct growth and yield tables, and on their defects and advantages. One of the main defects of growth and yield tables prepared previously in Central Europe is that the site quality classes for different tree species have been formed independently and using different principles. Thus, the yields of different tree species on a similar site can’t be compared. In addition, the quality classes of this kind of growth and yield tables and growth series are artificial.
The Society of Forestry in Finland (now Finnish Society of Forest Sciences) started to prepare new yield tables for the most important tree species in Finland in 1916. The new yield tables aimed to improve the yield tables made in Central Europe in two aspects. Firstly, the quality of the site of each sample plot was assessed on the spot and independently from the standing crop. Thus the sample plots of each site class in setting up the growth series can be treated as independent groups. Consequently, the quality classes are be the same for all tree species. Secondly, mathematical-statistical methods were used to determine which of the stands that belong to the same quality class belong also to the same growth series.
The PDF includes a summary in Finnish.