10 BULLETIlSr 697, U. S. DEPARTMENT OF AGRICULTURE. 



ment: How to Secure and Use Tree-Performance Records." In order 

 to make the present discussion complete, the following brief resume 

 of the methods used for obtaining the grapefruit performance-record 

 data is here given, 



TREE NUMBERS. 



The performance-record trees have been given individual-tree 

 numbers, consisting of the number of the block, the number of the 

 row, and the position of the tree in the row, counting always from 

 some fixed point, as, for example, the irrigation head. This number 

 is painted on the tree trunks, always in the same relative position, 

 with white-lead paint. The figures are made large and plain and 

 are so placed as to be easily legible and accessible. 



PICKING. 



The trees are picked by trained pickers from the regular crews 

 employed on the properties where the plats are located. Usunlly 

 the same men have picked the performance-record plats every 

 season. In this work all of the fruits of each tree have been picked 

 at one time. Owing to the fact that the eastern market season for 

 California grapefruit is best in midsummer, a condition which has 

 been recognized fully only recently by the California growers, the 

 time of picking the performance-record plats has been postponed 

 each year, until at the present time it begins during the latter part 

 of June. 



The fruits from the trees in the performance-record plats are, of 

 necessity, handled more often than is ordinarily the case. For this 

 reason, especial care has been used in handling, in order to avoid so 

 far as possible all mechanical injuries to the fruits. After the per- 

 formance-record observations have been completed, the crop of each 

 tree, except such samples as may be required for further study, is 

 included in the general field crop and sent to the packing house. 



ASSORTING. 



The fruits from the individual trees are'assorted into three grades, 

 viz, Ivory- White, Standard, and Cull. The Ivory- White or commercial 

 grade corresponds to a first and the Standard to a second grade. 

 The Ivory- White grade includes all of the most valuable commercial 

 fruits; the Standard, all of the blemished fruits, or those having poor 

 color, shape, or other inferior commercial characteristics, but suitable 

 for shipment to market; and the Coll grade, those fruits which for any 

 reason are not worthy of packing for the market. 

 • The work of assorting grapefruits according to size and grade has, 

 of necessity, been done by hand, as shown in Plate IV. No machines 

 such as are used with other citrus fruits are available for sizing Marsh 

 grapefruits satisfactorily for these investigations. In the perform- 



