112 FOOD FOR PLANTS 



each full-grown tree a mixture of 7 pounds of 14 per 

 cent, acid or superphosphate and 4 pounds of sul- 

 phate of potash, by working them into the soil ; after 

 which 4 pounds of Nitrate of Soda may be likewise 

 applied. The working of the soil must not be so deep 

 or thorough as to start the growth of the tree. An 

 excess of Nitrate is to be avoided, but the amount 

 mentioned is not too much. Nitrate of Soda is a pre- 

 digested Nitrogen. There is a danger of loss of 

 Nitrogen in other forms as they must generally be 

 made available as food, and during this comparatively 

 long process much of it may be lost by rains and 

 leaching, since they suffer in fact from many days of 

 long exposure to the adverse condition. 



In the case of your particular soil, it may well be 

 that it is sufficiently rich in potash, and therefore, 

 may not require a large application of it. In any 

 event, the grower must be governed by the condition 

 of his grove and the general character of soil and 

 climate in his particular locality. 



The early decay of orchards as well as failure to set 

 fruit buds, is largely a matter of lack of plant food. 

 Orchards should have Nitrate, applied early in the 

 season, as late supplies of Nitrogen are liable to cause 

 a heavy setting of leaf buds at the expense of next 

 year's fruit. The ordinary ammoniates are not satis- 

 factory for orchard work, as they continue to supply 

 available ammonia all through the season; not 

 enough in the early part of the year to properly set 

 the fruit, hence severe dropping ; too much late in the 

 year when none is needed and which causes the for- 

 mation of leaf rather than fruit buds. The soil be- 

 tween the trees should be regularly tilled, much as in 



