The Origin of our British Flora 



forests of Jed and of Dalton covered huge areas in the 

 south. When Robert the Bruce narrowly escaped from 

 his pursuers in Glen Trool, the impression which one 

 gets from the contemporary accounts is that the country 

 was covered with trees, probably of pine. 



At a much earlier date one finds frequent references 

 in Tacitus and other Roman writers to the Silva Cale- 

 donica of, apparently, great pine trees. 



Tacitus himself is much too flowing and literary in 

 his appreciation of the great Agricola for much trust to 

 be placed in his allusions, but the plain deduction from 

 his and other Roman authors seems to be that Scotland 

 was then a forest-clad, marshy, feverish country, which, 

 in their view, would never be of the least importance to 

 civilised man. 



The population seems to have been large, for it is the 

 fact that the Picts and Caledonians invaded England 

 before 120 A.D., about I38A.D., in 161 A.D., on the acces- 

 sion of Commodus, before 208 A.D., when Severus lost 

 50,000 men in Scotland, and frequently after that. 

 Moreover, there was a large population in Scotland long 

 before any Roman saw the country. There were great 

 Neolithic settlements which should surely have com- 

 menced at least 1000 B.C. 



So far as one could draw any conclusion from these 

 facts, the upper pine forest of the deposits is just the 

 Silva Caledonica of the Romans and the traditional 

 Scotch forest which was of pine in the uplands and of 

 oak in the lowlands. 



Its destruction could be satisfactorily explained simply 

 by the continual cutting and burning necessary to sup- 

 port a large population, and especially by the ravages of 

 goats, black cattle, and horses, which would prevent any 

 reafforestation. 



So the Romans and Scotch savages would seem to 



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