220 VEGETATION OF THE PEAK DISTRICT 



VIII. The Plant Formation of Clayey Soils. 



1. Association of damp Oak Woods {e.g., Quercetum roboris). 

 b. Sub-association of damp Oak-Hornbeam Woods. 



2. Associations of Scrub. 



3. Associations of Neutral Grassland. 



4. Associations of Swamps. Transitional to X. 



IX. The Plant Formation of Calcareous Soils. 



1. Association of Beech Woods on Chalk (Fagetum sylvaticae). 



2. Association of Yew Woods on Chalk (Taxetum baccatae). 

 ' 3. Association of Ash Woods (Fraxinetum excelsioris). 



4. Association of Ash-Oak Woods on calcareous clays and marls. 



' 5. Associations of Scrub. 



1 6. Associations of Calcareous Grassland {e.g., Festucetum ovinae) 



^ 7. Associations of Swamps. Transitional to X. 



X. The Plant Formation of Marshy Soils {i.e., soils subject to periodical 



inundations). 



1. Associations of Marsh Woods {e.g., Alneta, Saliceta). 



2. Associations of Marsh Scrub. 



3. Associations of Marsh Grassland. 



XI. The Plant Formation of Peaty Soils with alkaline Waters ( = the 



Fen Formation). 



1. Associations of Fens. 



2. Associations of Fen Scrub. 



3. Associations of Fen Woods. 



4. Associations of Fen Grassland. Transitional to X. 



XII. The Plant Formation of Peaty Soils with acidic Waters ( = the 



Moor Formation). 



1. Associations of Bog-mosses (Sphagneta). 



2. Associations of Moor Scrub. 



3. Associations of Moor Woods, e.g. (Pineta, Betuleta). 



4. Association of Rhyncospora alba. Transitional to XI. 



5. Association of Eriophorum angustifolium. 



6. Association of Scirpus caespitosus. 



7. Retrogressive Associations with Rhacomitrium lanuginosum. 

 ^8. Association of Cotton-grass Moor (Eriophoretum vaginati). 

 ^9. Retrogressive Associations with Vaccinium 3fyrtillus, Em- 



petrum nigrum, and Rubus Chamaemorus. 

 • 10. Association of Bilberry Moor (Vaccinietum myrtilli). 



• b. Sub-association of Vaccinitim Vitis-idaea. 

 ^11. Association of Heather Moor (Callunetum vulgaris). 

 '^12. Association of Grass Moor. Transitional to VII. 



XIII. The Plant Formation of Alpine Summits. 



1. Associations of Calcareous rocks. 



2. Associations of Non-calcareous rocks. 



