BUD SELECTION" IX THE VALENCIA OEANGE 
35 
by selections from progenies now in fruiting, which have been 
propagated from apparently superior parent trees or limb varia- 
tions, strains better yielding than any now in commercial cultiva- 
tion will be obtained. 
SUMMARY 
The individual-tree performance record studies of bearing Valen- 
cia orange trees which have been carried on since 1912 in established 
orchards located in southern California have shown that these groves 
consist of at least 12 strains of commercial importance, together 
with a number of others of minor economic consequence. The trees 
of these strains have either fruit or vegetative characteristics, or 
both, which serve to distinguish them from all other trees of this 
variety so far as known. 
In the course of these investigations it was found that certain 
Valencia trees had produced striking limb variations. In these in- 
stances the fruit or foliage characteristics of the limb sports were 
Fig. 22. — Very small ribbed Valencia orange fruits with persistent styles on a limb 
variation. Santa Paula, Calif., May, 1922. (Natural size) 
very different from the characteristics of the remainder of the trees, 
and when once identified they were easily recognized during subse- 
quent studies in these and other Valencia orchards. 
In these limb variations two conditions of development have been 
found: (1) Stable ones or those in which the entire limb variation 
is uniform in its fruit and foliage characteristics, and (2) unstable 
ones in which the limb variation has fruit or foliage normal as well 
as typical of the variation. 
The similarity of the fruits and foliage of the limb variations with 
those of entire-tree variations in established Valencia orchards sug- 
gested the probability that the tree variations were the result of the 
unintentional propagation in commercial nursery practice of limb 
variations occurring in otherwise normal trees. 
Propagations of a number of limb variations occurring in other- 
wise normal Valencia trees were made in the spring seasons of 1915 
and 1916. The resulting progeny trees were planted in the orchard 
of the Citrus Experiment Station of the University of California 
