68 



Food for Xhe clay soil probably does not contain enough 



^*^"^^ moisture and decaying vegetable matter to make the phos- 

 phoric acid in the basic slag available, so it would be folly 

 to attempt to use it there ; while the acid rock would not 

 give as good results on the black soil as the slag, although 

 the cost is greater. The quantity of either to apply on 

 ordinary soils is i,ooo pounds per acre very early in the 

 spring, so that in fitting the ground it will become very 

 thoroughly incorporated with the soil before the onion seed 

 is sown. 



The following table gives the actual field results of six 

 years' experiments with fertilizers and seven years with 

 manures at the rate of 30 tons per acre : 



Manure. Chemicals. 



Tons per acre, average 8.90 14.02 



Market value per ton, average ^18.16 $20. 52 



The crop grown with chemical fertilizers was 5.12 tons 

 greater per acre, a gain over the stable manure of nearly 58 

 per cent.; while the Nitrate crop averaged $2.^6 greater 

 market value per ton, an advance over the manure-grown 

 crop of 13 percent. The chemical fertilizers proved much 

 superior to the stable manure, though the latter contained 

 much more plant food, as the following table shows : 



Chemicals. Stable Manure. 



Ammonia as Nitrate 60 lbs. 360 lbs. 



Phosphoric acid 130 lbs. i 50 lbs. 



Potash 50 lbs. 340 lbs. 



Thus proving that the onion will thrive on a much' 

 smaller amount of actual plant food when it is supplied in 

 an immediately available form. 



Stable Manure and Artificial Fertilizer 

 Upon Fruit Trees. 



In this country the manuring or fertilizing of fruit 

 plantations is very commonly neglected, but in Europe 

 fruit trees are as regularly treated with plant food as staple 

 crops. According to the investigations of Professor 

 Barth-Colmar and Dr. Steglich, Dresden, the wood, foliage 



