CH. 11] WOODLAND ASSOCIATIONS 39 
WooDLAND ASSOCIATIONS OF GREAT BRITAIN 
The various plant associations which are known to occur 
among British woodlands are summarised below (cf. Moss, 
Rankin, and Tansley, 1910) :— 
I. ALDER AND WILLOow AssocraTIONs. On very wet soils. 
IL. 
A. On soils supplied with acidic waters. 
1. Alder and willow thickets of lowland moors. 
B. On soils supplied with basic waters. 
2. Alder and willow thickets of the East Anglian fens. 
C. On fresh soils subject to periodical inundations. 
3. Alder and willow thickets by stream sides. 
Oak anp Bircu Associations. On non-calcareous soils. 
D. On deep clays. 
4, Oak woods with Quercus Robur (= Q. pedunculata) dominant. 
Usually coppiced (see Moss, Rankin, and Tansley, 1910: 
118). Widespread throughout the lowlands of southern 
and central England. 
46. Oak-hornbeam woods with Q. Robur and Carpinus Betulus 
sharing dominance. Rather local in south-eastern England. 
Frequently coppiced. 
E. On dry sands and gravels. Not uncommon in the south and 
east of England. Locally coppiced. 
5. Oak woods with Quercus Robur or Q. sessiliflora dominant, 
either separately or in combination. 
6. Birch woods with Betula pubescens dominant, or with B. 
pubescens and B. alba (=B. verrucosa) in combination. 
7. Pine woods with Pinus sylvestris dominant. 
7a. Mixed woods of oaks, beeches, birches, and pines. 
8. Beech woods with Fagus sylvatica dominant. Local in the 
south of England. 
F. On the shallow soils of the older siliceous rocks. 
9. Oak woods with Q. sessilifora dominant. Very common on 
hill slopes in the north and west of Britain at altitudes 
below 1000 feet (305 m.). Locally coppiced. 
10. Oak-ash woods with @. sessiliflora and Fraxinus excelsior 
sharing dominance. Very local. They occur in the Lake 
District, where the rainfall is very high. 
11. Birch woods with Betula pubescens dominant. Local. They 
occur in the north of England as a zone above the woods 
of Quercus sessiliflora at altitudes between 1000 feet and 
1250 feet (381 m.). Much commoner in Scotland. 
12. Birch-ash woods with B. pubescens and Fraxinus excelsior 
sharing dominance. Local. They occur in the Lake 
District. 
