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potash and phosphoric acid. For potash we usually use 300 

 pounds per acre of high grade sulfate, and it is better applied 

 as early in the season as possible and plowed under. I 

 should favor plowing under all fertilizers, as it gets them 

 down where the feeding roots are, and where they will be 

 under such conditions as to make them most quickly avail- 

 able. Of course this is less important with the readily solu- 

 ble fertilizers, but even with these I should favor turning 

 them under. 



In phosphoric acid one has the choice of several different 

 forms, but probably the best two for the orchardist are basic 

 slag and one of the superphosphates or acid phosphates. 

 Where one is plowing the land I should favor the use of the 

 basic slag, as, in addition to the phosphoric acid, it contains 

 a large percentage of lime, which will assist in putting the 

 soil in good shape. It will run usually about 15 per cent to 

 17 per cent of phosphoric acid, and from experience in many 

 orchards it seems to be an admirable form. On the other 

 hand, where one is not able to plow the land, or for any rea- 

 son has decided not to, the superphosphate is the best form 

 of phosphoric acid, as it is readily soluble, and will therefore 

 get dowTi to the roots of the trees more quickly and more cer- 

 tainly than the basic slag. As to quantities per acre or per 

 tree, a good yearly application of the slag would be from 

 300 to 500 pounds per acre, or on scattering trees from 8 to 

 10 pounds per tree. Where the superphosphates are used the 

 quantity applied should vary with the source of the material 

 from which they were manufactured, but probably should 

 be from one-third to one-half less than of the basic slag. 

 These quantities are merely suggested as the usual ones ap- 

 plied, and it should be borne in mind that there is little dan- 

 ger in applying an over-dose of either potash or phosphoric 

 acid, as neither one leaches out of the soil to any extent, nor 

 does either one, when present in moderate excess in the soil, 

 produce the injurious effect on the orchard that an over- 

 supply of nitrogen does. They should be applied as early in 

 the spring as possible, and worked into the soil as much as is 

 possible with the method of culture adopted. 



