232 



As tlie whole wood was subjected to a fair amount of over- 

 head shell fire, the different effects on the various types of tree 

 could be observed and compared. The Silver Birch and Poplar 

 showed the most adverse, the Beech the least adverse, effects 

 under similar damage by exploding shells. 



The photograph (Plate XI.) obtained of the Beech (Fagus sylva- 

 tica) indicates to some extent the small amount of damage done to 

 it in spite of the fact that the whole trunk of the tree was most 

 generously peppered with shrapnel fragments. 



Most of the injuries appeared to have been inflicted on the 

 tree during 1915-16, and but little effect on its vitality was to 

 be seen. 



The bark renewal of the tree was extremely rapid. The base 

 of the trunk of this tree was also badly damaged, due, presum- 

 ably, to horses having been tethered close by at a recent date. 



The whole of the Beeches throughout the wood showed similar 

 powers of recovery after being considerably damaged* 



Similar injuries inflicted on the Ash (Fraxinus excelsior) in- 

 variably resulted in the injured branches dying off, but generally 





made a good recovery afterwards. In a few instances, 

 however, the more seriously injured trees lost the greater part 

 of the head, but showed signs of growing again below the injured 

 part, as seen in Plate VII., fig 2. 



As the injuries in the latter case were sustained during the 

 spring and summer of 1918, it 1ms still to be seen whether the 

 pollard growth will continue in subsequent seasons or whether 

 such growth was due merely to utilisation of the reserve materials 

 in the tree. 



The Poplars, white and Lombardy (Popuhis alba and P. nigra 

 var. pyramidalis), invariably died under the effects of even a 

 moderate amount of overhead shell fire, and this was particularly 

 noticeable among the roadside trees. 



The Silver Birch (Betula alba) similarly succumbed^ and 

 usually during the same season in which the damage was inflicted. 



Oak trees throughout withstood the damage very poorly, but 

 survived. Many that were injured in 1915-16 are still alive, 

 but linger on in very poor condition. 



The Hornbeam (Carpitius BetuJus) also withstood shell fire 

 very poorly and shoAved only faint signs of recovery. The frag- 

 ments of shrapnel usually 'penetrated into the trunk of a tree 

 to a depth of about 2 to 3 in., but in some instances they 

 were as deep as 5 in. A good example of healing of a deep 

 shrapnel wound is shown in fehe^photograph (Plate VII., fig. 1) of 

 an Oak tree some 18 to 20 in. in diameter. The shrapnel had 

 here penetrated to a depth of 5 in. and a fine healthy callus 

 had begun to develop round the edge of the injury. 



The effect of shell fire on trees, therefore, does not appear to 

 have the same adverse effect on a fairly hard wood of reasonably 

 quick growth, such as the Beech, as it has on the softer-wooded 

 trees of more rapid growth, surh as the Poplar, or on the harder 

 wood of slower growth such as that of the Oak. 



In addition, it was observed that the trees hit most frequently 

 were not neces-arilv the most seriously damaged one-, as in manv 

 cases it was not always the number of wounds that caused the 



