94 



timber at quite an early age. Investigations 

 made by me on some state property acquired 

 in the forest district of Freising l gave in three 

 samples 68 per cent., 70 per cent., and 73 per 

 cent. that is, an average germinating capacity of 

 7O'3 per cent. One litre of seed weighs 0*25 kilo 

 and contains 500,000 grains, so that i kilo con- 

 tains two millions. The warmer the climate the 

 greater must be the increase of atmospheric 

 moisture in the case of this tree, at least equal 

 to that which characterises oak locations. In 

 situations with humid air (such as on the sea- 

 coast and the north and east slopes of medium 

 mountain ranges, narrow valleys) a moderately 

 fresh soil will suffice for it. Under all other 

 conditions the demeanour of the Lawsoniana is 

 unfavourable, and it succumbs to its enemies, 

 to which, on so-called warm slopes, the branch 

 disease (according to Mayr, killing of the chloro- 

 phyl due to low winter temperatures) belongs. 

 Natural reproduction always is carried on sub- 

 ject to lateral or slight upper protection, so 

 that it should be planted in groups between 

 broad-leaved trees or common pines and Wey- 

 mouth pines, but not between firs and spruces, in 

 case it should be of equal age with its environ- 



1 Near Munich. Begun some twenty years ago by 

 Forstrat Bierdimpfel, they are being extended by Forstmeister 

 Striegel. 



