Suhspontaneous Pinewoods of Southern England 117 



Highland straths (broad valleys) and glens, extending 

 for considerable distances up the mountain slopes. The 

 former area is now very greatly restricted, but con- 

 siderable tracts of forest, largely open owing to heavy 

 exploitation of the timber, still remain in some places. 



It is of interest to note that both native and sub- 

 spontaneous pine is in this country apparently always 

 associated with heathland. The sub-spontaneous pine- 

 woods of southern England occur mainly on the heaths 

 of the Bagshot Sand and of the Lower Greensand, 

 though the pine sows itself fairly freely on some of the 

 Bast Anglian heaths and also on those of north-east 

 Yorkshire. In the Highlands of Scotland the native pine 

 woods seem to be developed on the same habitats as the 

 heath association, to which they give place when heavQy 

 cleared. The pinewood association is therefore naturally 

 included in the heath-formation. 



The sub-spontaneous pinewoods of the southern sands 



may be very briefly dealt "svith. In the 



EngUsh sub- neighbourhood of mature plantations or of 

 spontaneous , ,„ -, ,-, i ,■ ■ 



pinewoods. mature sell-sown woods thousands of pme 



seedlings in all stages of growth may fre- 

 quently be found colonising adjoining heathland, often in 

 company with the birch. The pine seedlings sometimes 

 push up from among fairly thick heather (Plate Via 

 and b). In this way many of these heaths are being 

 rapidly converted into pinewoods, the pine easily beating 

 the birch in the later stages of competition by reason of 

 the much deeper shade which it casts. The process is only 

 checked by the frequent heath and forest fires which occur 

 in dry summers and autumns. 



The close pinewood association is very poor floristically, 

 partly on account of the deep shade and partly because 

 of the thick layer of pine needles which carpets the floor 

 of the wood. The shade forms of Pteris aquilina and 

 Vaccinium Myrtillus often occur, and the silvery tussocks 



