Associated Trees of Quercetum sessilifiorse 125 



there in situations where it has obviously been planted; 

 and. it sometimes, no doubt, spreads from the plains for 

 some distance up the lower valleys. As a planted tree, 

 mixed with such undisputed aliens as the sycamore {Acer 

 Psevdo-platanus) and the larch (Larix decidua), it has 

 been observed so high as 1100 feet (c. 336 m.). 



No conifers are indigenous in these woods; but the 

 larch and the Scots pine (Pinus sylvestris) are frequently 

 planted. Other conifers which are occasionally or rarely 

 planted are the black or Austrian pine (P. austriaca), 

 the Douglas fir {Psevdotsuga Douglasii), and the Redwood 

 (Sequoia sempervirens) . As sub-fossil timber, the Scots 

 pine is occasionally found buried under the peat of the 

 southern Pennines ; and it is rather remarkable therefore 

 that the tree is not indigenous in the Pennine woods at 

 the present time. Even where planted, the Scots pine 

 does not here seem to be very prosperous, as seedling 

 pines are never abundant. It is clear that this species 

 does not thrive on the damp soils of the Pennines nearly 

 so well as on the drier heaths of the south of England. 



The beech (Fagus sylvatica), although an almost in- 

 variable constituent of the larger woods, has little claim 

 to rank as indigenous. In favourable seasons, ripe fruits 

 are formed even at an altitude of 1500 feet (457 m.); and 

 first-year seedlings are frequently seen. Older seedlings, 

 however, have not been observed ; and there is no evidence 

 to show that the beech rejuvenates itself in these upland 

 woods. 



The common birch {Betula tomentosa) is, on the whole, 

 the most common and the most constant 

 native trees associate of the sessile oak in these woods. 

 Forms or varieties with glabrous twigs are 

 not uncommon ; and the variety parvifolia (? = B. carpa- 

 tica) has been observed. Not infrequently the birch 

 becomes locally dominant in places where extensive 

 felling of the oak and no subsequent replanting has 



