CITRUS CULTURE IN PORTO RICO 



17 



uniformly transmitted through the bud. The fruit from some par- 

 ticular branch may prove to be more desirable than that from the 

 other branches on the same tree, in which case the buds should be 

 taken from the one branch only. Of course the records for one 

 year will not be as reliable as data covering a period of at least five 

 3 T ears. There are many tree records now on the island, and a com- 

 parison of them may yield valuable data leading to the establish- 

 ment of a foundation for future work. Planters ayIio have not yet 

 adopted the system of indexing their trees individually should do 

 so at once. They will soon learn of the benefits to be derived from 

 such a system and the importance of selecting bud wood from trees 

 whose records have been kept 

 for a number of years. Two 

 numbers should be painted on 

 each tree, one to indicate the 

 row and the other the number 

 of the tree in the row. 



DETERMINING THE VOLUME WEIGHT 

 OF THE FRUIT 



In bud selection the grower 

 usually judges the desirability 

 of the fruit without regard to 

 weight, measurements, or other 

 accurate tests, which is unsatis- 

 factory. The acidity may be 

 determined by titration and the 

 total solids by means of a 

 hydrometer, the methods of 

 determining which are well 

 known to most planters. The 

 weight should preferably be 

 ascertained by means of scales 

 that are correct to within the 

 limit of 1 gram. The exact 

 size may be ascertained by 

 means of a container shown in 

 Figure 8. The container is 

 filled with water until a few 

 drops escape from the spout, 

 when the measuring cylinder 

 is set under the spout. The 

 fruit is immersed in the water 



and is held down by means of the point of a nail. The number of 

 centimeters of water escaping from the container may be learned 

 from the cylinder and indicate the volume corresponding with that 

 of the fruit. The weight in grams, formerly ascertained, divided by 

 the volume in centimeters will give the density, the variations of 

 which are governed mainly by the thickness of the rind. • An orange 

 having a density much below 1 has a very thick rind, judging from 

 Porto Kican standards, and a grapefruit having a density below 

 0.85 has a thick rind. It is well to peel the fruit and weigh the rind. 



87036°— 30 3 



Figure 8. — Can and measuring cylinder for de- 

 termining volume weight of fruit 



