BUD VARIATION IN THE EUREKA LEMON. 



81 



of the typical pai'ont trees have been uniformly transmitted. Varia- 

 tions in some of the individual trees in these progenies, similar in 

 degree to those of the parent trees, have been found. However, no 

 mixture of strains has been discovered so far in the progenies. There- 

 fore, it can be safely stated at this time that it is practicable to iso- 

 late the different strains through bud selection 

 based upon individual-tree performance records 

 and intimate tree knowledge. 



TOP-WORKING UNDESIRABLE TREES. 



The healthy unproductive lemon trees of 

 undesirable strains in bearing orchards can 

 usually be successfully top-worked through 

 the use of bud wood selected from desirable and 

 superior performance-record trees. Figure 18 

 shows two such bud sticks before they have 

 been cut from the parent tree. Three bud 

 sticks cut from the tree and ready for use are 

 illustrated in figure 19. 



The top-working is usually best done during 

 the months of April, May, and June. As a 

 rule, in the instances under observation, the 

 best results have been obtained during May 

 and early June. Fall top-working is not usu- 

 ally done on account of possible frost damage 

 to the tender growth, except that it is the 

 practice of some growers to insert buds in the 

 trees to be top-worked during the late fall 

 and allow the buds to remain dormant un- 

 til spring. The advantage claimed for this 

 method is that if any of the buds do not unite 

 with the limbs in which they have been in- 

 serted and die during the winter new buds can 

 be used in the spring, resulting in a more uni- 

 form stand than with spring budding. Obser- 

 vations during the course of these investigations 

 do not bear out this contention, so that spring 

 budding is strongly recommended for top- 

 working. 



The trees selected for top-working should be so pruned as to allow 

 free access to the limbs m which the buds are to be inserted, as sho^\^l 

 in figure 20. The limbs for top-working should be selected from the 

 standpoint of furnishing a strong and suitable framework for the 

 new tops. Usually from three to five such foundation limbs are 

 necessary for the best results. The best place for the insertion of 

 135336°~20— Bull. 813 6 



Fig. 19. — Typical truit-bear- 

 ing bud sticks from a lemon 

 tree nf the Eureka strain. 

 The bud sticks after being 

 cut and trimmed should be 

 packed in slightly mois- 

 tened sphagnum moss and 

 held in a cool room until 

 needed for use. (One-half 

 natiu-al size.) 



