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1916 ANNUAL REPORT 



appearing fruit than one which is permitted to become more or less 

 dormant through lack of fertilizer, but it is quite certain that the semi- 

 dormant tree will carry its fruit with out dropping for a considerably 

 longer time. There is therefore a rather delicate adjustment to be made 

 in order to bring the tree into condition such that it will hold its crop 

 until late in the season and at the same time will not "go back" to an 

 extent that will be seriously detrimental to its further development or 

 jeopardize the crop for the following season. 



Following such applications of fertilizer as are made to restore the 

 tree to good condition after it has passed through the period of bloom 

 and fruit setting there should certainly be at least one further fertilizing 

 during the summer or early fall to provide the nourishment necessary 

 for the production of the crop. And it may be added here that the drain 

 on an avocado tree in bringing its fruit to maturity seems to be vastly 

 greater in proportion than the same effort on the part of a citrus tree. 

 The writer cannot vouch for the soundness of the theory, but it has been 

 his thought that this is probably due to the different character of the 

 fruit. In the case of any citrus, water constitutes a large percentage of 

 the fruit either by weight or volume, while with the avocado the propor- 

 tion of oils is much higher and it would seem reasonable that to supply 

 these components would be a heavier draft upon the tree. At any rate 

 the fact is certain that an avocado tree must be furnished with a suffi- 

 ciency of plant food if it is to be expected to produce full and regular 

 crops. 



Just how late in the season an application of fertilizer can be made 

 without bringing about a tendency for the tree to mature and drop its 

 fruit at too early a date depends somewhat on weather conditions. 

 Fertilizer applied to Trapp trees about the middle of August of the season 

 just passed, apparently had no detrimental effect as to the fruit holding 

 well, while an application of fertilizer given the same trees about the 

 first of September of the proceeding year was followed, within a few 

 weeks, by heavy dropping of fully matured fruit. The application made in 

 August of the present year was at the beginning of several weeks of dry 

 weather, while that of the previous season was followed by heavy rains 

 and these differences in moisture probably had considerable to do with the 

 effects of the fertilizer. 



This second problem is one of great importance to the Florida 

 avocado grower as between December 1 and December 15 the value of 

 his product not infrequently more than doubles and the premium to be 

 gained by being able to carry his fruit until the latest possible date is 

 well worth his very best efforts. 



It is our plan at Medora Grove to give the trees a heavy fertilizing 

 immediately after the crop has been picked and a light application 

 about the first of February, which brings them to their blooming stage in 

 good condition, quite thoroughly recuperated from their fast during the 

 fall. 



This program provides for five or six applications of fertilizer 

 during the year, which is probably one or two more than is given by most 

 growers, the difference being in the method of carrying the trees through 



