79 



25. Robinia pseiido acacia. 



The sylvicultural qualities of this tree, together 

 with its adaptability, have been so thoroughly 

 described in journals dealing with forestry that 

 there is hardly anything now to be said. This 

 species of timber tree can be grown both as high 

 forest and in coppice, and even on the poorest 

 soils, given the same climate as the sweet 

 chestnut and warm oak localities. It is espe- 

 cially useful for the afforestation of waste lands. 

 The Robinia may be recommended for mixing 

 with the pines on the fourth quality soil and 

 upwards, and it is also useful for underplanting 

 pines. In copse forest, where it suffers at times 

 from storms, new growth is made by root 

 shoots, which appear in great abundance where 

 its roots are cut by making trenches. The 

 property which its roots possess of assimilating 

 nitrogen from the air gives it the character of a 

 valuable soil-improving species of tree, which 

 should be more widely distributed in high forest 

 than appears to be the case at present. 



26. Ulmus americana. 



Apart from its greater rapidity of growth, this 

 elm shows no difference in its sylvicultural 

 peculiarities from the European mountain, Scotch 

 or witch elm, Ulmus montana. 



