THE MONTHLY BULLETIN. 



381 



Exports. 



In past years large quantities of citrus fruits have been exported to America, 

 Canada, Manchuria and Russia. The quarantine regulations promulgated in 

 recent years by the American authorities against citrus stocks and fruit from 

 the Orient because of the citrus canker have shut off this field of export com- 

 pletely. Naturally this has given rise to numerous protests from the growers 

 of Japan, who, as a rule, do not appreciate the great risk to the California 

 citrus industry from the introduction of this disease. 



Cultural Methods. 

 Because of the irregular terraced hillsides upon which citrus is usually grown, 

 and also because of the relative cheapness of labor, practically all cultural 

 operations are performed by hand. The trees ordinarily are considerably 



Fig. 125. Pest control in the citrus 

 orchards of Japan. Owing to the steep- 

 ness and the peculiar arrangement of the 

 terraces power sprayers are not used. 

 The photograph shows a bucket pump in 

 operation. (Original.) 



smaller than Navel and Valencia trees of California and are, therefore, 

 planted more closely together. Usually there are about one hundred and fifty 

 trees per acre, but with some varieties the number may be increased to over 

 two hundred. Clean culture is usually practiced, though in Schidzuoka and 

 Wakayama prefectures tea is often grown between the rows. Judging from the 

 appearances of the trees grown in this way, interplanting with tea is not a desir- 

 able practice, as the trees were invariably in poor physical condition and 

 produced only a light crop of fruit. Vegetables of various sorts are frequently 

 grown between the trees, and without any noticeable detrimental effects. 



Pest Control. 

 A great variety of pests are found attacking citrus in Japan, and the prob- 

 lems arising in their control are oftentimes very difficult. Much injury is done 

 to the trees by the citrus canker, the white fly, and various other insect 

 enemies. The canker is often combatted by the use of a Bordeaux spray, 

 applied with a knapsack pump, though with doubtful results. This is the only 



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