After critically reviewing earlier studies on soil properties and their influence on forest growth and yield, it seems that defining the forest yield could be possible by means of soil properties. To be able to do so, the site needs to be defined and delineated in some other way. It is also necessary to decide the right soil properties to study for the purpose.
For the classification of forest sites the results of soil analyses need to be compared with growth and yield data from the site. To further the practice of classification of forest sites by means of soil studies, four aspects need to be taken into account:
1) the site needs to be delineated beforehand according its vegetation, preferable with Cajander’s forest type classification
2) the experiments about soil needs to be done for as many properties as possible
3) the studied sites need to be as representative as possible in their class
4) there are as many samples for one site as possible studied
The volume 34 of Acta Forestalia Fennica is a jubileum publication of professor Aimo Kaarlo Cajander.