New York Agricultural Experiment Station. 527 



land. This leads to the statement of a conviction that has been 

 forming in the writer's mind for several years past. Namely, it is 

 becoming more and more apparent that cover crops alone in many 

 cases are not sufficient to supply tilled orchards with the humus 

 and nitrogen, humus in particular, that trees need and that the 

 deficiency must be made up by an occasional application of stable 

 manure, or by occasionally keeping the orchard in a clover sod for 

 a season. 



INFERENCES FOR NEW YORK APPLE-GROWERS. 



From the behavior of the Hitchings orchards, New York apple- 

 growers may infer that there are particular places, soils and economic 

 conditions under which the Hitchings method of sod-mulching apple 

 trees may be used advantageously. Since the prerequisites for the 

 success of the method, as indicated by the Auchter and Hitchings 

 orchards, are not very generally found in this State, the situations 

 in which sod may be given preference over tillage should be set forth 

 with exactitude. These are: 



1st. Orchards on steep hillsides where land would wash badly under 

 tillage may be kept in sod. — As we have tried to show in the para- 

 graphs on surface washing, page 523, cultivation may be so managed 

 that there are few commercial apple orchards in New York in which 

 cultivation need be prevented by soil erosion. It is probable that 

 clover or some other legume might be substituted advantageously 

 for the blue grass and orchard grass of the Hitchings method where 

 sod is desired to keep water from wearing the land away. 



2d. Land covered with rocks, whether steep or not, must often be 

 kept in sod because of the impossibility of tilling. — There are not a 

 few such orchards in New York. 



3d. The Hitchings method is best suited to soils having consider- 

 able depth. — It is adapted only to soils in which grass roots and tree 

 root do not come in too intimate contact and too direct competition 

 for food and moisture. The commercial apple orchards of New York 

 are at present on lands the top soil of which averages less than a 

 foot in depth. On these shallow soils the Hitchings method will 

 prove a failure. 



4th. Soils must be retentive of moisture. — To sustain trees at their 

 best under the Hitchings method, soils must not only be deep but 

 must be very retentive of moisture, or have the water table compar- 



