64 FORESTRY IN GREAT BRITAIN AND IRELAND. 



followed, in order, by tundra, steppe and, finally, by forest, the 

 latter continuing to the present time, but the three periods do not 

 seem to be strongly marked in the British Isles. At the height 

 of the forest period probably the greater part of the country was 

 covered with forest, except the highest moimtains. Remnants 

 of oak and Scots pine have been found up to an elevation of 

 2,500 feet above sea level. The indigenous forests have been 

 classified as follows : — 



(1) On alluvial deposits : Willow, alder, ash and poplar, chiefly 



along rivers. 



(2) On dry sandy soils : Oak, beech, birch, Scots pine ; on 



sandy heaths of Surrey, Hants and Dorset. 



(3) On soils over old silicious rocks : Oak and birch ; in the 



hilly districts of western and northern England, Wales and 

 southern Scotland, they were of great extent. 



(4) Indigenous pine forests : In many parts of the British Isles 



particularly in the eastern highlands of Scotland. 



(5) Beech woods : On the chalk downs of South England, also 



on the carboniferous limestones ; associated with the 

 beech was the yew. 



(6) Ash woods : On fissured limestone, in Somerset, Derbyshire 



and in Ireland. 



(7) Oak forests : On the clay soils of lowlands. 



(8) Oak-ash forests : In lowland districts on marl soils. 

 Great changes have occurred in these forests, due partly to 



nature and partly to the action of man. The forests on alluvial 

 soil have made room for agriculture. The ash, beech and birch 

 forests have degenerated or been planted with conifers. The oak 

 forests on old silicious rocks have, to a great extent, disappeared 

 by changing into grassy or bracken-covered hills ; parts have been 

 destroyed or felled for fuel, timber, and charcoal making ; parts 

 have been maintained as coppice ; other parts were replanted with 

 conifers, such as larch, Scots pine, spruce and lately with exotic 

 species ; other parts remain in the hilly district ; the soil of all 

 these parts is fit for the growth of first-class coniferous timber. 

 The indigenous pine forests are gradually being cut. Of the beech 

 forests considerable remnants are found in the Ohiltern Hills. 

 Of the ash woods and oak-ash woods small fragments remain, 

 the rest having been converted into pasture lands. The oak 



