BUD VARIATION IK 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 Sharael, 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. 
