1910.] PUBLIC DOCUMENT — No. 31. 19 



hold. If these soils are deficient also in lime, as is likely to lie 

 the case, an application at the rate of 1,500 to 2,000 ponnds 

 per acre before the trees are set, and a further apjdieation at the 

 rate of 600 to 800 jwunds per acre once in five or six years, will 

 prove useful. 



Under this system clover will become abundant in the orchard 

 kept in sod, while such cover crops as soy beans, vetches or 

 clovers will thrive if tillage is practiced. Under either the sod 

 or tillage system, therefore, a sufficient supply of nitrogen will 

 be brought within the reach of the trees. 



Formula No. 2 will prove well suited for use on the medium 

 or heavy soils. It supplies no nitrogen, but creates soil con- 

 ditions peculiarly favorable for the coming in of clovers 

 in the sod, or nitrogen-gathering cover crops in tilled orchards. 

 Under these conditions it seems likely that sufficient nitrogen 

 will be brought within reach of the trees. If, however, the 

 growth of the trees is not satisfactory, a small amount of nitrate 

 of soda, 100 to 125 pounds, may be added. 



Formula No. 3 differs from ISTo. 2 only in supplying the 

 slag and low-grade potash in smaller amounts. This formula is 

 suggested for use in those cases where it is convenient and re- 

 garded as desirable to employ some manure in the orchard. It 

 is not the writer's belief that it will usually pay to purchase 

 manure for such nse, but in so far as it is available as a home 

 jn-oduct its use in moderate quantities may be advisable, 

 jManure, however, supplies nitrogen in relative excess for fruit 

 trees. It seems wise, therefore, to supplement it with materials 

 like slag meal and low-grade sulfate of potash, which will supply 

 additional phosjihoric acid, lime and potash. It is not the 

 writer's belief that it will usually be best to nse manure in top- 

 dressing orchards in annual amounts in excess of about 1^2 

 cords per acre. 



Sod or Tillage. 

 The fact that the orchard in which the experiments npon 

 which this article is based have been tried has been kept in sod 

 since 1895 should not be regarded as indicating that the sod 

 system is held to be always superior to the tillage system. Both 

 systems have their advocates. The question whether sod or 

 tillage is better cannot be regarded as settled ; indeed, as an 



