COMPOSITION OF VARIOUS TREES 157 



margins of deep yellow ; Acer negundo variegata 

 has beautiful silver-edged leaves ; and Acer 

 Californica aurea, perhaps one of the most 

 beautiful trees of recent introduction, has brilliant 

 golden foHage, and is a striking feature in any 

 landscape. 



The juice of Acer saccharinum of North 

 America yields when evaporated maple-sugar. 

 The juice is obtained by tapping the trees in the 

 spring, and a well-grown tree yields about four 

 pounds of sugar every season. 



Rhamnus {Rhamnus catharticus, buckthorn, 

 Natural Order, Rhamnacese) is a hardy deciduous 

 shrub. It grows in ordinary soils in sunny or 

 shady shrubberies. 



The ashes of the buckthorn contain in 100 

 parts : — 



One ton of Rhamnus extracts 23 lbs. of mineral 

 matter from the soil. 



