As shown by the list of forest-types, both the appearance and the 

 comparative prevalence of the forest-types varies considerably in 

 different parts of the country. This is further shown by the follow- 

 ing figures which are based on the results of valuation-surveys by 

 line carried out at different times, the rarer forest-types being inclu- 

 ded in the nearest general type. 



c,r A Parish of Kub- 

 Forest-type Savo and malahti in Cen . South 



tral Finland La P land 



Oxalis-Majanthemum type 6.55 % 



Oxalis-Myrtillus type . 32.02 11.36 % 



Myrtillus type 28.62 49.28 9.24 % 



Vaccinium type 29.74 27.67 5.68 



Calluna type 3.07 11.69 8.53 



Geranium -Dryopteris type 3.37 



Hylocomium-Myrtillus type .... 19.18 



Empetrum-Myrtillus type 18.12 



Oladina type 35.88 



Thus, the further north one comes, the rarer are the best forest- 

 types, and in North Finland the predominating types are such as 

 are never or only nominally met with in the southern part of the land. 

 In this connection the existence of the different forest -types is a key 

 to the reasons for the difference in productivity between the various 

 parts of the country. The proportion of appearance and prevalence 

 of the forest -types varies, however, even in the same district, depend- 

 ing, among other reasons, on the degree of lime in the soil, partly 

 also in the bed-rock, the situation of the land at different heights, 

 whether on the watersheds or near larger waters, and finally, on the 

 varying soils, etc., etc. In the grove-forest areas, of which more is 

 spoken in the part on forest management areas, the soil is usually 

 comparatively rich in lime. 



Nature of the Forests. 



The composition of Finland's forests with regard to the differ- 

 ent species of trees is affected by the geographical distribution of 

 the various species and their relation to the many forest-types, and 

 the results of civilization, such as cutting and fires. The former factor 

 is of small importance elsewhere than in Lapland; where the bounda- 

 ries of the two most common trees in the forests of Finland the pine 

 (Pinus silvestris) and the spruce (Picea excelsa) are situated compara- 

 tively far apart (Fig. 1). Of the commoner forest trees Betula 

 odorata species of birch, the aspen (Populus tremula) and 



