BIRDS IN RELATION TO AGRICULTURE 177 



tain of the native sparrows, piles of brushwood or logs 

 should be left in sheltered places where they need not prove 

 an eyesore, and they could be covered with vines. Piled 

 logs not only serve as nesting-places but as shelters in the 

 inclement weather that often occurs in the spring after the 

 return of the earlier spring migrants. 



Nesting-boxes or Bird-houses. — One of the most important 

 methods of providing nesting-places is by the distribution 

 of nesting-boxes or bird-houses. In certain European coun- 

 tries the provision of nesting-boxes for birds constitutes a 

 recognized adjunct of forest protection, and such artificial 

 nesting-sites are distributed by the thousand in forests 

 owned by the state and private individuals. The cutting 

 out of hollow and rotten trees which follows proper forestry 

 management renders such a procedure necessary as a means 

 of replacing the natural nesting-places so destroyed. 



The greatest exponent of the practice of bird-protection 

 was, undoubtedly, the late Baron von Berlepsch, and to 

 him we are indebted for the splendid example he has given 

 at Seebach, in Germany. His ideas have been adopted by 

 various states in Germany and in countries where the pro- 

 tection of birds and the provision of nesting-boxes constitute 

 an important and necessary adjunct of forestry methods. 

 An instance, given by Baron von Berlepsch, of the practical 

 value of bird-encouragement, may be quoted. The Hainich 

 wood, south of Eisenach, which covers several square miles, 

 was stripped entirely bare in the spring of 1905 by the cater- 

 pillars of the oak leaf -roller {Tortrix viridiana). The wood 

 of Baron von Berlepsch, in which there had long been nest- 

 ing-boxes, of which there are now more than 2,000, was un- 

 touched. It actually stood out among the remaining woods 

 like a green oasis. At a distance of a Uttle more than a 

 quarter of a mile farther, the first traces of the plague were 

 apparent, and at the same distance farther on still it was in 

 jfuU force. It was plain proof of the dist^c^ the tit9 and 



