176 Studies in Forestry [CHAP. vni. 



ence. But the initial costs of sowing are apt to be mis- 

 calculated ; and the subsequent filling in of blanks with 

 transplants often brings up the actual cost to more than 

 would have been the initial expense had planting been chosen 

 as the original method of forming the crop. 



Plantations have, in general, notwithstanding the inter- 

 ference and disturbance that takes place before the plants 

 have thoroughly established themselves, a more rapid develop- 

 ment in youth, and especially a more energetic growth in 

 height, than young crops resulting from natural regeneration ; 

 whilst those formed artificially by sowing occupy a position 

 between these two. These results are explainable by the 

 greater amount of soil-preparation connected with both forms 

 of artificial production and reproduction, and, in the case 

 of plantations, with the larger amount of individual exposure 

 to light, air, and warmth, together with a less prolonged 

 struggle with weeds and rank growth of grass. 



Natural reproduction is, on the whole, much cheaper than 

 either of the artificial methods. And, when properly conducted, 

 it affords greater protection against frost, drought, and injurious 

 insects ; whilst, at the same time, it maintains the surface-soil 

 subject to the least possible variations in its quality, its cover- 

 ing, and its productive capacity. As greater density of the 

 young crop is usually attained, the thickets grow up remark- 

 ably free from branches ; but the superior quality of the 

 straight-grained timber is apt to be counterbalanced by the 

 danger to which the young crop is exposed if the poles are 

 allowed to be drawn up too quickly in their mutual struggle 

 for light and air. This struggle for existence is more severe 

 and of longer duration than in the case of crops formed 

 artificially, and especially of plantations; hence careful, oft- 

 repeated clearing and weeding in thickets, and thinnings in 

 pole-forest, are absolutely essential for the avoidance of over- 

 crowding. 



For the successful accomplishment of natural regeneration 



