240 REPORT OF OFFICE OP KXPRRTMKNT STATIONS. 



apiinst the Sail Just'' scale. It :ii)pears from the invoslifrations of 

 tliis station that the wash exorcises a (U'striictive eifcct u|)()ii the 

 scale insects in two ways: (1) Directly throii<;li its sohihle com- 

 jKMinds actiii«j: soon after its application as a contact poison, and (2) 

 (hi-oM^h its nioi-c slowly sohiblc conij)onn(ls which form a crnst, and 

 thus prevent the deNclopment of the youn<>; scales. When the wash 

 was applied with snlphui- in the pi-opoi-tion of one part to ten j)arts 

 of lime, .Japan ]>iuni trees were not injured even in the summer. 

 Encoura«^in<>- results were early obtained from the use of the self- 

 l)oilin«T mixtui'e prepared with caustic soda as a suhstitutv for the 

 boiled mixture. It was found that the California wash is not only 

 a. very etiective insecticide, but also exercises considerable fungicidal 

 effect. Its value as a fungicide was somewhat increased when it 

 was conil)ined with a solution of copj)er sulphate forming a combined 

 insecticide and P)ordeaux mixture. The time reconnnended for its 

 ai)plication was just before the opening of the buds or the time 

 usually set for the application of Bordeaux mixture. No injury was 

 observed from the -winter application of California wash to apple, 

 peach, pear, or plum trees. The only eifect observed upon the tree 

 was a slight delay in the appearance of the leaves. The same station 

 carried on quite extensive experiments to determine the value of the 

 lime-sulphur-caustic soda wash when used in the place of Bordeaux- 

 arsenical mixtures for a general orchard treatment. It was found 

 that this wash was a safe and reliable remedy for scale insects and 

 that it exercises, to a considerable extent, an action against the devel- 

 opment of apple scab, pear j^sylla, and peach and pear mites. The 

 self-boiled mixture, however, did not give as uniformly satisfactory 

 results as the California wash prepared by external heat. One appli- 

 cation of the wash during the dormant season was sufficient to reduce 

 greatly the injuries from early spring leaf -eating caterpillars, such 

 as the bud moth, and also to reduce the injuries from codling moth. 

 As used against the last-named insect, however, it was inferior to 

 Bordeaux-arsenical mixtures. The station continued, its experiments 

 with the California wash with particular reference to a determina- 

 tion of the effects of fall applications upon fruit and leaf buds, as 

 well as upon San Jose scale. The orchards in wdiich these tests were 

 made consisted of standard varieties of various fruits. In one orchard 

 Avhich was not infested with San Jose scale, the ai)plication of sul- 

 phur washes caused a slight diminution in the amount of bloom and 

 foliage of peach and plum trees, lliis effect was less marked after 

 the use of lime-sulphur wash than when other contact insecticides 

 were used. It was also .observed that with the advance of summer 

 there was a decided increase in the amount of new growth and foliage 

 upon the treated trees. The fruit yield was greater on treated than 



