Iv] GRASSLAND ASSOCIATIONS 111 
Pyrus Aucuparia Ajuga reptans 
Crataegus Oxyacantha Digitalis purpurea 
Lathyrus montanus Melampyrum pratense (agg.) 
Vicia sepium Holcus mollis 
Viola Riviniana 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 typical and abundant 
plants which occur in the Nardus grassland: full lists of grass- 
land species are given at the end of the chapter :— 
Dominant 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 Cytisus scoparius 
