May, 1931] Studies in Economics of Apple Orcharding 47 



pected. The total vegetative growth made by an acre of year old trees 

 is very small indeed. The operatio^ of tillage would probably put as 

 much linear growth on one 10-year old tree as on 20 trees at one year 

 of age ; and from this point of view, the tillage of an acre is twenty 

 times as effective if applied to the older trees. 



It would seem to be more economic to grow the tree under a heavy 

 mulch system for ten years and then cultivate to incorporate organic 

 matter. It may be possible to get along with less fertilizer in a cul- 

 tivation program; but on the other hand, it is doubtful if much 

 headway can be made in increasing content of organic matter without 

 fertilizer. Then too, if there is any saving in fertilizer due to cul- 

 tivation, the amount of saving would be larger when trees are older. 

 From the point of view of organic matter, improvements made now 

 for use ten years hence involve an expense in waiting. Might it not 

 be better to reverse the usual procedure of cultivating the first ten 

 years, and instead carry the trees along in mulch for this period and 

 then cultivate occasionally to incorporate organic matter? Plowing 

 under the thick sod formed by liberal use of nitrate of soda is one 

 of the most efficient methods of adding organic matter to the soil. 



When trees are very young, a small amount of mulch, 40 lbs. per tree, 

 will be very effective. Later when trees are ten years old, three times 

 as much mulch would be needed. Even with only 27 trees per acre 

 and Avith liberal application of fertilizer, the mulch is likely to be in- 

 adequate when the tree is ten years old. At this age cultivation will 

 control moisture and make it possible to reseed a new sod which will 

 yield heavier mulch the next and succeeding years. 



Occasionally other factors than moisture control may need consider- 

 ation. In recently tilled fields, witch-grass may interfere with root 

 growth and make some sort of cultivation or mechanical mulch neces- 

 sary. Then, too, occasionally the vegetative growth becomes such a 

 mat that the nitrate fertilizer applied does not get to the tree roots, 

 being absorbed by the grass vegetation instead. 



Inter-Tillage 



Farms 2 and 4 did considerable inter-tillage in the young orchards ; 

 and in this case, the cost is somewhat complicated by joint production. 

 When trees are set 108 to the acre there is ordinarily not mulch 

 enough to get good tree growth ; and if one is to have trees this thick, 

 perhaps tillage is the best way. But when trees are so thick, it is 

 doubtful if inter-tillage is practical. It is a case of choosing between 

 having 5 acres of potatoes and beans and strawberries in the orchard, 

 or taking another tract of 5 acres and putting these crops on it. 

 The cost of the use of 5 acres of land is insignificant, and if the 5 acres 

 is made more fertile by application of fertilizers and cultivation, this 

 is as valuable to crops of beans, potatoes, etc., as it is to future crops 

 of fruit. In other words, it is a doubtful practice to take the earnings 

 from other crops and apply to the cost of growing apples when one has 

 the option of putting these crops on other land under conditions where 

 they could be produced more economically. 



When an orchard is set out on land that is worth tilling, if the trees 

 are set 27 to the acre and if there is a good amount of hay per acre, 



