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BETTER FRUIT 



Page 5 



during the period of hot, burning sun- 

 light. Bordeaux mixture gave rather 

 indifTerent results in fungous control 

 and its heavy deposit on the apples pre- 

 vented their normal coloring. In the 

 rainless-summer climate of the Wenat- 

 chee Valley, Bordeaux applied in July 

 was still present on apples picked in 

 October. It is likely that the use of 

 neutral Bordeaux would not result in 

 such marked effect on the color, but 

 this material was not used in the experi- 

 mental work. Instead, ammoniacal cop- 

 per carbonate was used. This material 

 leaves no deposit on the fruit and hence 

 does not restrict natural coloring. It 

 gave practically as good control as Bor- 

 deaux mixture, but neither of these 

 sprays approached the efficiency of 

 lime-sulphur or certain other sulphur 

 sprays. 



The following spraying program, 

 based upon the results of the Wenat- 

 chee spraying experiments during the 

 seasons of 1915-16-17, is recommended. 



The first application should consist 

 of lime-sulphur solution, diluted 1 to 50, 

 and .should be applied when the buds 

 are in the "pink," that is, when the in- 

 dividual buds are separated and just 

 before the blossoms open. The delay of 

 infected buds prevents an earlier spread 

 of the disease, hence an application of 

 fungicides at this time protects the trees 

 through the blossoming season — during 

 the period when the first crop of new 

 spores is produced and scattered. If 

 the spraying is well done and all of the 

 new leaves thoroughly coated with 

 lime-sulphur, spores on them will be 

 prevented from germinating. At the 

 same time the application of the caustic 

 lime-sulphur spray to existing patches 

 of mildew destroys established centers 

 of infection. At this time, however, the 

 foliage is expanding very rapidly and 

 new leaves are continually being pushed 

 out, so that complete protection is 

 assured for a short time only. An ideal 

 flght against mildew would consist in 

 providing a proper spray coating to all 

 new leaf surface as rapidly as it 

 appears. But it is impracticable to 

 accomplish this from a commercial 

 standpoint. 



The second application should follow 

 as soon as the petals fall. For this 

 spray lime-sulphur at the same dilution 

 may be efficiently combined with lead 

 arsenate, used for codling-moth control. 

 A prejudice against this combination 

 spray exists in some sections, due to an 

 idea that the poison is rendered less 

 effective against the codling moth and 

 that danger of spray injury is in- 

 creased. This prejudice is not war- 

 ranted by the facts. The combined 

 spray not only provides a great econo- 

 my of time and effort in application 

 where both insecticide and fungicide 

 must be used, but it has been repeatedly 

 demonstrated that it is more ellicient 

 than separate applications. This com- 

 bination spray is in general use 

 throughout the country where lime- 

 sulphur and arsenate of lead are used 

 against apple scab and codling moth. 

 The combined spray, with lime-sulphur 

 diluted 1 to 50, does not increase the 

 danger of spray injury. In the Wcnat- 

 chee experiments no serious injury ever 



Figure o — Biancli fiuui a Joiiallian liiK-, slio\' iiig a lenniiial killed by the infection of the previous 



year. Note that the petals are beginning to fall from the healthy blossoms on the lower portion, 



while the blossoms from the infected buds near the terminal twig are not yet open. 



developed from combining lime-sulphur 

 and lead arsenate. Serious injury has, 

 however, followed the combination of 

 lead arsenate and sodium sulphur prep- 

 arations put out as substitutes for lime- 

 sulphur. 



The first two applications describe<l 

 "above are most important, and in any 

 efficient program for mildew control 

 they cannot be dispensed with. Under 

 some conditions further spraying for 

 mildew may not be necessary, but ordi- 



narily at least one more application 

 ought to be made. The time for this is 

 about three weeks after the second 

 application, or "calyx spray." If the 

 spring has been rainy, and if a serious 

 infection persists, continued spraying 

 through the summer may be necessary. 

 The interval betwen ths applications 

 should not be greater than three to four 

 weeks. 



Until after the calyx spray the very 

 efficient sulhpur sprays, especially lime- 



