88 BIILLETIlSr 813, U. S. DEPAETMENT OF AGPJCULTUKE. 



The method of keeping the individual-tree performance records is 

 to pick each tree separately, assort the fruits, count and weigh them; 

 make descriptive notes, photographs, and drawings of the trees, 

 foliage, and fruits; and record these data so that after an adequate 

 number of studies have been made conclusions as to varietal, strain, 

 and tree behavior can be safely drawn. 



In these investigations eight strains of the Eureka lemon have been 

 studied, their characteristics described, and the performance of 

 typical individual trees recorded. 



Some of the lessons taught by these studies include the discovery 

 of the importance of bud variations and the comparative value of 

 the different strains arising from them, the necessity for and methods 

 of isolating the valuable strains and eliminating the unprofitable 

 ones through bud selection, the determination of the characteristics 

 of the trees, flowers, and fruits of the different strains, and the 

 origination and introduction of improved methods of propagation 

 for conserving and improving the production of the lemon industry. 



The desirable strains can be isolated through bud selection based 

 on tree-performance records and intimate tree knowledge. 



Undesirable healthy trees in established orchards can usually be 

 successfully top-worked by the use of carefully selected buds. 



The undesirable unhealthy trees can be replaced in established 

 orchards through replanting with desirable ones when proper atten- 

 tion is given to the preparation of the planting holes and adequate 

 care in irrigation and fertilization is given to the individual trees. 



Only fruit-bearing bud wood from superior parent trees selected 

 on the basis of their performance records and intimate tree knowledge 

 should be used for propagation or for top-working. 



In California, as a result of these investigations a department of 

 bud selection has been established by the California Fruit Growers' 

 Exchange, a cooperative organization of citrus growers, whereby 

 reliable bud wood from superior performance-record lemon trees 

 can be obtained by all growers and propagators. 



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