BUD VARIATION IN". THE VALENCIA ORANGE. 5 



variety, have expressed genuine surprise when some of the bud 

 variations of foliage and fruits occurring on their trees have been 

 pointed out to them. As a matter of fact, while bud variations have 

 been known to exist in trees of this variety for some time, their 

 frequency and importance have not been fully realized until very 

 recently and as a result of these investigations. 



Twelve important strains of the Valencia variety have been found 

 and described during these investigations. Several other minor and 

 less frequent variations have been found from time to time, but, 

 so far as is now known, they are of little significance or importance 

 in commercial orchard practice or in the present studies. 



The total number of strains existing in the Valencia variety is not 

 known. Additions are continually being made to the list, as knowl- 

 edge of the variety grows and the extent of the investigations widens 

 to include observations of a larger number of trees. 



The extent of the occurrence of diverse strains of the Valencia 

 variety in established bearing orchards has been found to be even 

 greater than the occurrence of similar variations in Washington 

 Navel groves. The percentage of off-type trees, i. e., marked varia- 

 tions from the best or Valencia strain, found in individual com- 

 mercial orchards is practically the same as was found in Washington 

 Navel orange orchards (from about 10 to approximately 75 per 

 cent), 1 but a larger proportion of the Valencia orchards have shown 

 the higher percentages of trees of variable strains. 



The name Valencia has been applied to the best strain of the 

 variety, because, as nearly as can be determined, it is similar in type 

 of tree and of fruit to the original Valencia introductions into Cal- 

 ifornia which were propagated on account of their superior quality 

 and productiveness. This strain bears the heaviest crops and the 

 most desirable fruits of any of the strains of this variety under ob- 

 servation. It is the strain upon which the reputation of the variety 

 has been founded and which under present conditions is the most 

 desirable for cultivation in California. 



As a rule, the younger Valencia orchards show a larger proportion 

 of trees bearing inferior fruits than the older orchards. This con- 

 dition indicates that the prevailing methods used in propagating 

 this variety have resulted in the perpetuation of an increasingly 

 large proportion of trees of undesirable strains. 



OBJECTS OF THE INVESTIGATIONS. 



The objects of the investigations reported in this bulletin are (1) 

 to ascertain the variations which have taken place in the Valencia 

 orange through bud variation and to learn the comparative value of 



1 Shamel, A. D., Scott, L. B., and Pomeroy, C. S. Citrus-fruit improvement: A study of bud variation 

 in the Washington Navel orange. U. S. Dept. Agr. Bui. 623, 146 p., 16 fig., 19 pi. 1918. 



