THE CONTINENTAL FLORA OF SOUTH SWEDEN 341 



The forest and mountain districts of South Sweden, and also large parts of 

 the low-lying forest tracts of Central Sweden, usually lack the climatic and 

 edaphic conditions for the above mentioned oak and grove slopes. The thin 

 foliferous forests which we can here think of as a natural vegetation are of quite 

 a different character. On suitable slopes, and also in the natural forest edges, 

 we should here meet with comparatively thin mixed forests, in which birch and 

 aspen were the dominant kinds of trees. Owing to human intervention, these 

 types of forest have obtained an immensely increased distribution, and, next to 

 the coniferous forests they are the most important types of forest in South 

 Sweden. In Swedish they are called »hagar» [which seems to correspond to one 

 of the dialect meanings of the I^^nglish word »hag»]. 



It is in the east of Sweden, that a type of forest which falls under this head, 

 a mixed birch forest rich in Calainagrostis arundinacea, finds its main distribution. 

 Its ground vegetation is formed of mesophilous and comparatively heliophilous 

 grasses and herbs. The general distribution of this type of forest in Middle Europe 

 is clearly continental; and besides Calamagrostis itself it has several species of 

 continental distribution (Campanula cervicaria, Laserpitium latifolium, Melampyrum 

 nemorosum, Ranunculus polyanthemos, Selinum carvifolia); see Plate 22. It is 

 of interest to note that the commonest mesophilous thinned foliferous forest in 

 Central Russia seems to have as its distinctive species Calamagrostis arundinacea 

 and Melampyrum memorosum. 



In the north-eastern parts of the South Swedish highlands this type of vegeta- 

 tion appears pretty generally on slopes with a southerly exposure. In the less 

 elevated parts of Ostergotland, in Sodermanland, in Uppland, and also in parts 

 of Vastmanland and the south of Gastrikland I have seen this type of vegetation 

 abundantly distributed, with a mode of occurrence which strikes me as possibly 

 being its natural mode. It is met with on the edges of coniferous forests which 

 occupy regions with Archaean rock or moraine rich in boulders, and which outside 

 these regions are replaced by clayey ground, marshes or lakes. In a forest 

 district in Uppland situated 2 — 4 miles (Swed.) north-west of Upsala, in the 

 parishes of Vange, Skogs-Tibble, Jarlasa, Jumkil, Balinge, and Vittinge, where, 

 as far as one can judge, the vegetation may still show much of its natural 

 character, there is a district which is especially worthy of study. Large areas 

 of marsh ground, which are now for the m.ost part drained and cultivated, and 

 some small lake basins alternate with Archaean rock tracts or low boulderous 

 moraine tracts covered with coniferous forests. The old shore-zones are occupied 

 by foliferous forests or mixed forests, in the ground vegetation of which the 

 leading part is played by Calamagrostis arundinacea. 



In Table 5, Appendix II there are given a number of analyses (Columns I 

 and I — 8) cf foliferous forests rich in Calamagrostis arundinacea from different 



