40 VEGETATION OF THE PEAK DISTRICT [CH. 



% 



13. Birch-pine woods with B. alba; B, pubescens and Pinus 



sylvestris var. scottica sharing dominance. Local and 

 confined to mid-Scotland. 



14. Pine woods with Pinus sylvestris var. scottica dominant. 



Local and confined to mid-Scotland. 



III. ASH AND BEECH ASSOCIATIONS. On calcareous soils. 

 G. On deep marls or calcareous clays. 



15. Ash-oak woods with Fraxinus excelsior and Quercus Robur 



sharing dominance. Abundant in the south of England. 

 Usually coppiced. 



H. On shallow calcareous soils on hill slopes of the fissured limestone 

 rocks. 



16. Ash woods with Fraxinus excelsior dominant. Frequent in 



the west and north of England up to about 1000 feet 

 (305 m.), and local on the chalk. 



17. Ash-birch woods with Fraxinus excelsior and Betula pubescens 



sharing dominance. Local on the upper slopes of hills of 

 Carboniferous Limestone in the north of England. 



I. On shallow and very calcareous soils on chalk rock. 



18. Beech woods with Fagus sylvatica dominant. Frequent on 



the chalk escarpments in south-eastern England. 



Of the woodland associations above enumerated, two are 

 well developed on the southern Pennines, and three others are 

 only moderately well represented. The two former are the 

 association of Quercus sessiliftora on damp, shallow, siliceous 

 soils, and the association of Fraxinus excelsior on shallow 

 calcareous soils ; and these woods are described in some detail 

 in this chapter. The woods which are only moderately well 

 represented on the southern Pennines are the association of 

 Quercus Robur on deep sandy soils, the association of Betula 

 pubescens on damp, shallow, siliceous soils, and the alder-willow 

 thickets of stream sides. Some transitional and intermediate 

 woods also occur, and these will be referred to in the proper places. 



The relationships of these associations may be conveniently 

 set out in the following form : 



Alnus glutinosa and Salix spp. ALDER- WILLOW 



dominant THICKETS 



Quercus Robur dominant) _ . . ^ _ 



WOODS WITH { x> / -, j \ Oak woods OAK AND 



Q. sessihfiora dominant I v 



* } D- i J f BlRCH WOODS 



Betula pubescens dominant Birch woods j 

 (Fraxinus excelsior dominant ASH WOODS 



