Fertilizers for Peach Orchards 15& 



of plant-food removed, of course, would have been corre- 

 spondingly more. 



The estimated total amount of plant-food withdrawn by 

 an acre of 108 trees is of course hypothetical. The number 

 of trees to the acre varies considerably with different growers, 

 and within certain limits probably the larger the number 

 the greater the plant-food requirement. On the other hand, 

 trees planted 16 by 16 feet would probably begin to cro\j'd 

 long before they were ten years old and they would, there- 

 fore, not be likely to be as large and vigorous as trees that 

 had more space. Hence the plant-food requirements to 

 the acre would cease early in the life of the orchard to be 

 definitely proportionate to the number of trees where close 

 planting and the consequent crowding occur, in comparison 

 with a tree that grows without competition with others. 



The estimated annual plant-food demands of the tree 

 that was analyzed in the New Jersey work are illuminating 

 and instructive as is also the length of the new twig growth 

 in different years. In all these calculations the amount of 

 plant-food in the tree when it was planted as a one-year- 

 old is ignored, since it was so small as to be negligible. 



The estimated annual demands during the ten-year period 

 that enter into the consideration appear in Table VII, also 

 the length of the new twig growth made each year. 



It is to be noted that during the first four years, while 

 the tree was making most of its growth, there was a gradual 

 increase each year in the plant-food removed from the soil. 

 The extremely small amounts of the different elements taken 

 the first year is also of interest since it suggests that if the 

 soil is in reasonably fertile condition when the trees are 

 planted, there is little likelihood of their needing commer- 

 cial plant-foods the first season. In the following six years 



