EXTIRPATION OF HERBAGE. 117 



are then fit for being planted in moorland. They 

 should never be allowed to remain more than two 

 years in their seed-bed. 



If stronger plants are required to subdue a cover 

 of furze, or to extirpate any other rank herbage, they 

 should be allowed to stand two years in nursery lines. 

 As the plant ought not to be allowed to remain for a 

 longer term than two years in the seed-bed, the same 

 with the transplanted plants, which must not be kept 

 in nursery lines longer than two years additional, 

 when they will generally stand from two to two and a 

 half feet high, and will be strong enough for the roughest 

 kind of forest ground. If two-year old seedlings are 

 put into nursery lines and allowed to stand for two 

 years they will generally reach three feet. As before 

 stated, although the larch is deciduous, no tree is so 

 useful in annihilating rough herbage, and on this 

 account it is a most valuable tree. 



In the best situations adapted to its growth, the 

 larch has been known to attain a height of forty feet in 

 twenty years, but thirty feet is about the average which 

 must be counted upon for that period in most cases. 



The larch is very subject to attacks from insects, 

 the most obnoxious of which is the Coccus laricis, 

 which infests it mostly in low-lying situations, being 

 least injurious where there is a free circulation of the 

 atmosphere, and also when the plantation does not 

 consist entirely of larch trees. 



It is also occasionally attacked by atmospheric 

 blight, which occurs at different stages when the tree is 

 in leaf, which shows its effects in the following summer 

 by a want of foliage, and the presence of numerous 

 dead twigs throughout the tree. 



