BUD VARIATION- IK THE EUREKA LEMON. ( 
PLAN OF THE INVESTIGATIONS. 
These investigations have been carried on by means of individual- 
tree performance records. The term "performance record" is here 
used to mean a systematic record for a period of several years of the 
yield and behavior of individual trees. This record includes accu- 
rate notes of the number, the commercial quality, and the variability 
and other characteristics of the fruits produced by the individual 
trees. It is usually accompanied by descriptive notes and photo- 
graphs, or drawings, showing the characteristics of the habit of 
growth, the leaves and flowers, and the position or arrangement of 
the fruits on the trees. Individual- tree performance records for at 
least two consecutive and normal seasons on lemon trees which have 
reached full bearing age are considered necessary in order to deter- 
mine the value of the trees for commercial fruit production. Similar 
records for at least four years are advisable, in order to furnish an 
adequate basis for the selection of superior trees as sources of bud 
wood for propagation. 
The performance records presented in this bulletin have been made 
from full-bearing trees located in successful commercial orchards 
where the conditions have been particularly favorable for compar- 
ative individual-tree studies. It has been possible to compile these 
records only through the hearty cooperation of the owners of the 
orchards selected for study. The picking of the fruits has usually 
been done by members of the regular picking crew. The assorting, 
weighing, and counting have been done by the writers in the orchards 
immediately after the fruits have been picked. The crops of fruit, 
after the records have been finished, have been turned in with the 
crop from the orchard as a whole, except such specimens as have 
been needed for further study. Owing to the additional handling 
necessary for the classification of the fruits, particular care has been 
used in order to avoid as far as possible all mechanical injuries, which 
frequently lead to decay and consequent loss to the growers. 
The conditions considered in the location of the individual- tree 
performance-record plats were as follows: (1) The production of 
successful and profitable crops of fruit; (2) location on virgin land, 
in order to avoid any influence of previous cultural treatments; (3) 
protection from cold, strong winds, or other climatic causes of tree 
and fruit injuries; (4) the absence of radical pruning, rebudding, 
top-working, or other similar tree treatments; (5) freedom from or 
the effective control of diseases and insect pests; (6) uniform irriga- 
tion and cultural practices during the entire history of the orchard; 
(7) reliable information concerning the history of the buds used in 
the propagation of the trees and the kind of stocks; (8) the prospect 
of settled ownership for a period of years; and (9) the absence of 
apparent local environmental factors influencing tree behavior, in 
