FKOST PROTECTION IN LEMON ORCHARDS. 
27 
borne in mind, however, that the trees in this particular orchard were 
in a very vigorous and healthy condition at the time of the freeze, 
and with the exception of lack of heating had always received excel- 
lent care, which probably accounts for their rapid return to normal 
production. If the orchard had not received as good care or had the 
trees been in a less healthy growing condition, it is possi- 
ble that they might not have returned to normal produc- 
tion so soon. 
In addition to the data covering these two plats, obser- 
vations made in the other nonheated and heated orchards 
in 1914 showed that there was very little relative differ- 
ence in the number of fruits produced the second year by 
the trees which were heated in 1913 as compared to the 
nonheated trees. 
From these investigations it appears that the main 
effect of protecting trees during one season of low 
temperatures is in the saving of the crop for the cur- 
rent year, and that as a rule where the trees are in 
vigorous condition and receive good cultural treat- 
ment they will return to normal production at the end 
of one year. 
t 
Jm 
J 
COMPARISON OF THE EUREKA AND LISBON VARIETIES. 
j_ The two important varieties of lemons grown in 
California are the Eureka and the Lisbon. In order 
to secure some definite infor- 
mation as to the behavior of 
comparative plats in nonheated 
orchards, two blocks of trees, 
plats 2 and 3, were located, re- 
spectively, in Lisbon and Eu- 
reka lemon orchards. Both 
orchards were operated by the 
same man, the two plats under 
^ ,/~. T, ^x, V, rx . observation were only a short 
Fig. 14.— Diagram sho\\ing the number of frozen and . . *^. 
merchantable fruits produced on plat 2, a nonheated distance apart at practljCally the 
acre of Lisbon lemon trees, and plat 3, a nonheated ^.^^^ altitude, and, as far aS 
acre of Eureka lemon trees. The figures here shown i i i • i i 
are taken from Tables VI and VII, which give the COuld be detcrmmcd, the COudl- 
estimated production by grades for each month's ^'^j^g ^^^^ ^^ nearly Uuiform in 
picking for these plats during the calendar year 1913. . *^ 
each orchard as it was possible 
to obtain. Both the orchards received gome benefit from heaters in 
neighboring protected groves. A record of the production by grades 
during the calendar year 1913 for the nonheated Lisbon orchard is 
given in Table VI and for the nonheated Eureka orchard in Table 
VII. In figure 14 the number of frozen and merchantable fruits 
produced on each of these plats for the calendar year 1913 is given. 
