148 MANURES FOR FRUIT TREES 



The wood of Quercus contains 0*05 per cent, of 

 copper/ which, according to MacDougal,^ was 

 visible as reddish-brown particles in the tracheides, 

 vessels and medullary parenchyma. Demargay ^ 

 found, by means of the spectroscope, traces of 

 vanadium, molybdenum, chromium, and zinc in the 

 ashes of oaks, pines, poplars and vines ; and the 

 author has confirmed this investigation. 



Oleander {Nerium oleander, Natural Order, 

 Apocynacese) is a greenhouse flowering shrub with 

 evergreen leaves. It prefers a soil composed of one 

 part each of well-rotted dung, silver-sand and leaf- 

 mould, and two parts of sandy loam. 



The ashes of the oleander contain in 100 parts : — 



The leaves of the oleander contain neriin, which 

 is allied to digitalin. The flowers are red, crimson, 



" A. B. Griffiths, Gom/ptes Bendm de VAcadimie des Sciences de 

 Paris, tome 131, p. 422. 



2 MacDougal, Botanical Gazette, vol. 27, p. 68. 



3 DemarQay, Comptes Rendus, tome 130, p. 91. 



