76 ELEMENTS OF SYLVICULTUBE. 



PECULIAKITIES OF GBOWTH. The seedof the silver 

 fir is rather light and its wings enable it to be scat- 

 tered far and wide ; its cover is very thick, and the 

 young plant is very delicate. It remains unharmed 

 under cover up to thirty or forty years of age, and 

 even beyond that. In its true habitat it is not 

 much exposed to spring frosts, but it dreads heat, and 

 is easily killed before it has developed side branches, 

 that is, up to the age of three or four years. The 

 tree throws out a long tap root where the ground 

 is sufficiently deep ; but it soon produces strong lateral 

 roots, which allow it to establish itself and thrive 

 in superficial soils and even on rocky ground. 



A free, moist soil, of a sandy or calcareous nature 

 is best adapted to the silver fir. It avoids clayey 

 and damp soils, where rot speedily attacks its roots. 



The growth of the silver fir is very slow at first, 

 while it is not fairly verticillated, i.e., until about ten 

 years old ; from this moment it shoots up rapidly ; 

 its growth in diameter is never rapid, remains 

 uniform for a considerable time, and becomes slow 

 again at the age of eighty to a hundred years. At 

 low elevations, and in temperate climates, it shoots 

 up rapidly in height as soon as the first verticel 

 appears, but it dies early. 



The silver fir lives for several centuries, and is one 

 of our tallest trees, sometimes attaining the height 

 of 150 feet ; its diameter at six feet from the ground 

 seldom exceeds four feet. 



USES. The wood of the silver fir serves a variety 

 of purposes. It is largely used for beams and rafters 

 of houses ; its transverse strength is considerable, 



