Oak-birch heath Association 



101 



"ree layer (dominance often incomplete). 



Querous Kobur 



Q. sessiliflora (and 

 hybrids) 



Betula alba ( = B. verru- 

 cosa) 



B. tomentosa (and ' 



hybrids) 



Pagus sylvatica 



Pinus sylvestris (local 

 subspontaueous) 



Ilex Aquifolium 



Pyrus Aucuparia 



Castanea sativa (locally 

 planted, rarely subspon- 

 taneous) 



Qiiercus Cerris (occasion- 

 ally planted, very rarely 

 subspontaneous) 



Prunus Cerasus 



Pyrus Mains 



P. Aria 



Shrubs. 



CratseguB monogyna a 



Prunus spiuosa a 



Ulex europaeus la 



Bubus Idseus o 



R. cffisius o 



Eubus spp. i 



Cytisus sooparius o 



Ehamuus Frangala o 



Janiperus communis 1 



Salix caprea f 



S. cinerea f 



S. aurita f 



Lonicera Periclymenum a 



Ground vegetation. As we should expect in the case 

 of an association which represents a transition from one 

 formation to another the ground vegetation shows a 

 medley of forms, some belonging to the dry oakwood, 

 many to the heath association, while species of the grass 

 heath also occur, since dry oakwood in process of de- 

 generation, but in which the dry peaty humus charac- 

 teristic of true heath has not been everywhere established, 

 naturally tends towards the association of grass heath. 

 No attempt will therefore be made to give a complete list 

 of the ground vegetation of oak-birch heath, but a few 

 of the most characteristic and abundant species may be 

 cited. 



Calluna vulgaris (where the 

 light is sufficient) d 



Vaccinium Myrtillus (in 

 shade) il 



Erica cinerea Id 



Pteris aquilina a and Id 



Deschampsia flexuosa 

 Agrostis canina 

 Teucrium Soorodonia 

 Poteutilla erecta 

 Polygala serpyllacea 

 Melampyrum pratense 



