178 Forestry Quarterly. 



became worse, this deterioration being indicated for instance by 

 the southward withdrawal of the hazel. 



In Germany for a long time and into historic times the oak 

 remained in possession, but finally the beech crowded it back. 

 The spruce which used to be indigenous to northwest Germany, 

 did not return even into Denmark, coming into Sweden from the 

 northeast. 



The portions of Bohemia, Moravia and Lower Austria which 

 were not glaciated, and hence retained a relatively mild climate, 

 show, soon after the ice age, beech, oak and hazel, with which 

 pine, spruce and fir were associated. 



In the Alps the same change took place as in the northern 

 areas except that the forest of the oak period remained decidedly 

 a mixed forest and that the periods were of shorter duration. 



During the stone age, as the rubbish heaps show, the flora of 

 North and Middle Europe consisted almost exclusively of broad 

 leaf types and most of the charcoal consists of oak (74%) while 

 the beech did not yet exist in Denmark. Here it is found with 

 assurance not earlier than the iron age, perhaps in the time of the 

 Romans. The stone age, then, and the oak period cover each 

 other, and it would appear that man did not exist in Northern 

 Europe for thousands of years after the ice age. Before, the clim- 

 ate was too rigorous, the soil mostly swampy and unfavorable 

 for man's existence. 



The pile buildings in Switzerland exhibit all the species now 

 existing excepting larch, Pinus Cembra, and spruce, although the 

 latter existed, but fir seems to have been most common ; the larch 

 immigrated later. The stone age here coincides with the beech 

 period, the beech establishing itself here earlier than farther north. 



The prehistoric changes are then characterized by the fact that 

 the more frugal intolerant species were gradually displaced by 

 the more demanding which by their shady character improved 

 the soil, while during the time of man the opposite has been the 

 result of his interference. 



A more detailed account of the phenomena described above in 

 Cieslar's article may be found in the works of Axel Blvtt, 

 Nathorst, Rekstad, Gunnar Anderson, Sernander, A. Schulz and 

 others. 



These works have recently been reviewed by Jens Holmboe 



