CHAP, ix.] Tending of Woods 207 



warm methylated spirits. Nowadays, however, the simpler 

 method of coating over the surfaces with coal-tar, slightly 

 thinned with oil of turpentine, finds general adoption owing 

 to its cheapness. The coating of tar will only bite into the 

 surface satisfactorily whilst the wood is relatively free from 

 sap ; hence it should be administered either towards the end 

 of October, immediately after the vital functions of the foliage 

 have been completed, or at any rate some time during the 

 first half of winter. Unless the removal of the branches takes 

 place in autumn or early in winter, the experiments made by 

 Professor R. Hartig of Munich tend to show that, in addition 

 to the tar not obtaining a good hold on the wound-surface, the 

 condition of the woody tissue is such as to make it less able 

 to resist the penetration of fungoid, disease-producing spores. 

 Practically, the same principle holds good here as in regard to, 

 the thinning of young tree-forest ; for it is much better to thin 

 out branches to a moderate extent only, and then repeat the 

 operation subsequently if necessary, than to endeavour to effect 

 the object in view by one coup de main. 



The cost involved by the operation varies, in each particular 

 case, according to the local rate of wages and the handiness of 

 the workmen, the species of trees, the height at, and the extent 

 to, which the branches are to be removed, &c. ; but in Germany 

 it has been found to vary generally in amount from about \d. 

 to 2d. per stem for sawing off the branches and tarring the 

 wound-surfaces. In Britain, it will, for various reasons, prob- 

 ably cost quite the double of this amount ; but, even then, it 

 may, under certain circumstances, prove a highly remunerative 

 operation if judiciously conducted. 



With regard to the remunerativeness of the removal of 

 branches, Alers, who invented the patent long-handled saws 

 now usually employed in the operation, estimated that if begun 

 in the thirtieth year of age of the crop (coniferous ?), and re- 

 peated every five years till the fiftieth year, at a cost of about 

 i\d. per stem, the net results at eighty years of age, after 



