514 



Journal of Agricultural Research 



Vol. XII, No. 8 



Table VII. — Influence on orange production of different mulches in basins and by furrow 

 irrigation and cultivation. Experiment II. Picked JuTie, 1917 



Soil treatment. 



Average for 



each or;ianic 



substance 



with and 



without 



lime. 



Basins with alfalfa mulch alone 



Basins with alfalfa mulch and lime. . . 



Basins with manure mulch alone 



Basins with manure mulch and lime. . 

 Cultivated with manure alone, disked 

 Cultivated with manure and lime 



4.8 

 4.0 



2-5 



It is not known that the trees used in this experiment differed in 

 yields previous to the installation of this experiment. However, as no 

 individual tree picking records had been kept previous to the experi- 

 ment, the comparative yields shown in Table VII do not carry the force 

 they would if they could have been compared with the previous perform- 

 ance of the same trees. In comparing the fruit production in experi- 

 ments I and III, it seems safe to infer that the results obtained in Ex- 

 periment II were indicative of the effect of the different organic mate- 

 rials used. 



It will be noticed in Table III that the percentage of humus in the 

 manured basins was slightly higher than that in the basins mulched 

 with alfalfa, a result agreeing with that obtained in Experiment I. 



No appreciable difference in the color of the fruit from the trees dif- 

 ferently treated was discernible. 



Experiment III. — The block of 60 orange trees used in this experi- 

 ment had been used in a study of individual tree performance by the 

 Office of Horticultural and Pomological Investigations, Bureau of Plant 

 Industry. Individual tree records for the previous six years had been 

 obtained, and these were kindly furnished by the Riverside officials of 

 that Office. The picking records of the 191 6-1 91 7 crop are given in 

 Table VIII, together with the basin treatments. The basins were in- 

 stalled and mulched in October, 191 5. 



No effect of the lime on fruit production could be definitely deter- 

 mined; hence, the yields of all the trees mulched with the same organic 

 matter have been averaged, including both limed and unlimed trees. 



The alfalfa-mulched trees produced more fruit than the manure- 

 mulched trees, which result agrees with the results obtained in Ex- 

 periments I and II. It does not appear from Table VIII that any 

 legume whatever is superior to a nonlegume or to manure. The basined 

 trees mulched with sweet clover and bur clover did not produce as much 

 fruit as those mulched with alfalfa, bean straw, manure, or barley hay. 



