FROST PROTECTION IN LEMON ORCHARDS. 



27 



Q^ ^:f?c//yzF 



borne in mind, however, that the trees in this particuhir 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 



lUl 



COMPARISON OF THE EUREKA AND LISBON VARIETIES. 



I 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 

 ^ ,, ~. ^. . .V. V ^r . observation were only a short 



Fig. 14. — Diagram snowing the number of frozen and . •mi 



merchantable fruits produced on plat 2, a nonheated distance apart at practically the 



acre of Lisbon lemon trees, and plat 3, a nonheated ^^^^ altitude, and, as far aS 



acre of Eureka lemon trees. The figures here sho%vn. . :: 



are taken from Tables VI and VII, which give the COuld be determined, the COudl- 



estimated production by grades for each month's + JQjj^g were aS ncarlv Uniform in 



picking for these plats during the calendar year 1913. . "^ 



each orchard as it was possible 

 to obtain. Both the orchards received some 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. 



