SHELTER 1 OR DECIDUOUS TREES. 153 



proper distance. And, secondly, We must plant 

 considerably thicker than when firs are the nurses, 

 because the young trees must depend on one anotha: 

 for shelter, after they attain the height of five or six 

 feet. 



In many parts of Scotland, planting by contract 

 is much in use. Nurserymen are the persons who 

 generally undertake jobs of this kind, and they en- 

 gage to furnish the plants, and put them into the 

 ground, at a certain sum per acre. In making such 

 bargains, the age of the plants, their varieties, the 

 distances between them, and the number of each 

 kind to be used, are specified ; and the contractor, 

 for the most part, engages to uphold his work for a 

 certain number of years ; that is, to put in fresh 

 plants in all the deficiencies that may occur during 

 the stipulated period. This last condition is the 

 best security that can be taken for the works being 

 properly executed at first. 



Planting by contract will, in general, be found 

 the most economical plan of any, in propagating 

 those species which answer with that variety of the 

 notching or slitting system last described, in the 

 preceding section but one. The reason is, that 

 nurserymen have always at command a number of 

 hands, who are either already expert at this mode of 



