41 



the manufacture of paper. The young growing 

 trees are peculiarly liable to injury and, indeed, 

 destruction by the larvse of the Cossus ligniperda. 

 It is only in the Rhine Valley ^ that we find a 

 large area of poplar coppice. The growth of 

 these poplars, more particularly isolated trees in 

 avenues, is really astonishing and, according to 

 Kisling,2 nineteen trees of this species fifty-two 

 years old and raised at Koslin, averaged some 

 3J f m.3 of timber each. In the lowlands of the 

 Rhine and Main, Walther found the price to be 

 2 2 marks per fm., and I found one could get 

 30 marks per f m. at Forchheim. 



20. Prunus serotina, Ehrh., Late-blossoming 

 Cherry, Black Cherry. 



This tree, also, has been known a long time in 

 Europe, and has enjoyed great favour for deco- 

 rative purposes. The wood produced from it 

 shows the same red heart as that of the American 

 cherry-tree. Generally speaking, it does not yield 

 any valuable timber planted in parks, so that no 

 comparison can be made as to the respective 

 usefulness of the German and American serotina 



' Walther, "Die kanadische Pappel in der Main-Rhein- 

 Ebene," "A. F. u. J." 1895, p. 67. 



= "Anbau der kanadischen Pappel," "A. F. u. J.," 1898, 

 p. 251. 



3 = 39-1 — a cubic foot, literally one festmetre, one solid 

 cubic metre. 



