IV] GRASSLAND ASSOCIATIONS 111 



Pyrus Auciiparia Ajuga reptans 



Crataegus Oxyacantha Digitalis purpurea 



Lathyrus montanus Melampyrum pratense (agg.) 



Vicia sepium Holcus mollis 



Viola Riviiiiana Luzula pilosa 



Conopodium denudatum Orchis mascula 



Heracleum Sphondylium Scilla non-scripta 



Whilst opinions may differ as to whether or not the 

 grassland just described is wholly or only in part due to man's 

 interference, it appears to be generally accepted that such tracts 

 were formerly clothed with forest; and Warming (1909: 326) 

 even goes so far as to say that "were the human race to die out," 

 the grasslands of the lowlands of north Europe " would once 

 more be seized by forest, just as their soil was originally stolen 

 from forest." As regards the Nardus grassland of the hill-slopes 

 of this district, it seems incontestable that it is an association 

 which has, on the whole, resulted from the degeneration of oak 

 and birch woods. The fundamental conditions of the habitat 

 have been but slightly altered in the process ; and, therefore, 

 the oak and birch woods, the Nardus grassland, and the various 

 transitional stages of scrub are placed in one and the same 

 plant formation. 



The following is a list of the more t3^ical and abundant 

 plants which occur in the Nardus grassland : full lists of grass- 

 land species are given at the end of the chapter : — 



Dotninant species 

 Nardus stricta 



Sub-dominant species 

 Deschampsia flexuosa 



Locally sub-dominant species 

 Pteris aquilina 



Locally abundant species 



Ulex Gallii Festuca ovina 



Agrostis vulgaris Juncus effusus 



Less abundant and rarer species 



Botrychium Lunaria (local) Potentilla erecta 



Blechnum spicant Lotus corniculatus 



Rumex Acetosella Cytisua scoparius 



