BUD VARIATION IN THE WASHINGTON NAVEL ORANGE. 7 
Tree-census observations in navel-orange orchards in California 
show a general average of about 25 per cent of trees of diverse strains, 
most of which are inferior to the Washington as regards both the 
amount and the commercial quality of the fruit. As a rule, the 
younger orchards show a larger proportion of trees bearing inferior 
fruits than the older orchards. This condition indicates that the 
prevailing methods used for the propagation of the Washington 
Navel orange variety are causing the deterioration or "running 
out" of the variety as a whole through the perpetuation of an in- 
creasingly large proportion of undesirables 
OBJECTS OF THE INVESTIGATIONS. 
The objects of these investigations are (1) to ascertain the varia- 
tion which has taken place in the Washington Navel orange through 
bud variation; (2) to determine the extent to which undesirable 
variations have been propagated, as shown by the percentage of such 
undesirable trees existing in the present bearing groves; and (3) 
through improved methods of propagation to control the extent to 
which undesirable variations shall enter into the population of future 
commercial Washington Navel orange groves. 
PLAN OF THE INVESTIGATIONS. 
These investigations have been carried on by means of individual- 
tree performance records and observations. 
The term " performance record" is used here to mean the record 
of the number and the commercial quality of fruits borne by indi- 
vidual trees during a period of years. 
The term " performance-record plat," as used in connection with 
these investigations, means a group of trees grown under comparable 
conditions, selected for the purpose of determining the relative 
behavior of the trees by means of individual-tree records of pro- 
duction, observations, and descriptive notes and records. 
The individual-tree performance records made during these investi- 
gations were secured by giving each tree a number, by marking the 
trees annually with cloth streamers to prevent their accidental pick- 
ing by the regular ranch picking crew, by picking each tree sepa- 
rately and assorting its fruits according to grade and size, by weigh- 
ing each lot of fruit of each size and grade, by counting the fruits 
of each lot, and by recording these data on forms arranged especially 
for this purpose. In preparation for the work of assorting the fruits 
the season of 1909 was largely spent in citrus packing houses study- 
ing the grading standards in use in such houses at that time. Pre- 
liminary to each season's work since then, similar studies have been 
made in order to true up and improve the judgment of the observer 
when securing the investigational performance records. 
