174 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 



being shot off in so large a proportion as to constitute a danger 

 for the maintenance of the stock, and in France by the simple 

 fact that the numbers have altogether been greatly reduced. 



It is interesting to note that rabbits, which have hitherto 

 throughout Prussia only ranked as game in Hanover and Hesse 

 (the two provinces annexed in 1866), are now dismissed altogether 

 from the class of "animals fit for sport"; and quite rightly, too, 

 for rabbits can never be anything else than vermin so far as 

 forestry is concerned. 



Among the more directly practical articles, which are very few 

 in number compared with those of an academic or scientific 

 character, there is an interesting one by Forstmeister Lang on 

 " The Leading Points to be Kept in View in making Thinnings." 

 Even though it deals with German conditions, and is not 

 applicable to our British woodlands, its leading points may be 

 thus summarised, as indicating what may now be considered 

 to be the modern method of thinning in extensive forests:— 



(a) General Principles to be kept in view — 



1. Crop-increment is dependent on the nutrition of the 



various individual poles or trees. 



2. As the total amount of food absorbed from the soil by 



the crop apparently cannot be much increased by 

 thinning, but can only be enhanced by increase in the 

 leaf-area (foliage), the latter ought to be the first 

 object aimed at. The maximum leaf-area and the 

 maximum insolation of the foliage will be attained 

 in a crop when the individual tree-crowns extend as 

 far down as possible, and touch each other at their 

 edges ; and this is therefore the condition to be 

 aimed at in thinning, as being that best calculated 

 to produce the maximum increment for the given 

 soil and situation. 



3. But where it is also desirable to combine quality with 



quantity {i.e., where timber pays better than fuel), 

 then the crown of foliage must be kept as high up 

 as practicable, and not allowed to extend far down 

 the stem. 



4. Both of these two conditions can to a certain extent 



be attained by making the thinnings partly among 



