36 MASS. EXPERIMENT STATION BULLETIN 226. 



1. A thorough application of the calyx spray. This is very important. 

 L'pon it depends freedom from "blossom end" injury, and lessening the 

 danger of a large second brood. 



2. The cover or post-calyx spray is almost equally important. It de- 

 mands even more care from the grower as to the proper time of ap- 

 plication. Upon this depends protection over the long period during which 

 larvae are appearing, and relief from early "side worm" injury. 



The exact date for this spray, and the number of applications that 

 may be necessary cannot be stated absolutely. These must be determined 

 each season, as they are governed largely by weather conditions From 

 the experience we now have, two applications at intervals of two weeks 

 after the calyx spray have given excellent results. A third application may 

 be advisable should the season be imusually "early." 



3. If the season is "early," there will be the probability of a large 

 second brood. The bulk of this brood apparently comes about the first 

 of August each year, whatever the type of season up to that time. With 

 a brood of such size as that of 192.5, a special application in early August 

 is necessary to avoid .serious late "side worm" injury. 



TESTS OF LIME-SULFUR SOLUTION AND 

 SOME OF ITS SUBSTITUTES AGAINST SAN JOSE SCALE 



BY A. I. BOURNE 



While under eastern conditions, at least, lime-sulfur solution has long 

 been recognized as the standard dormant spray for the control of 

 San Jose scale, yet fruit growers are much interested in the various dry 

 powders now offered as substitutes for the concentrated solution. Trans- 

 portation charges are less, there is no danger of freezing and no loss from 

 leakage. Used in strengths recommended, these dry powders furnish less 

 polysulfide sulfur than does the concentrated liquid used at standard dilu 

 tion of one part to eight parts of water. 



This situation led the Experiment Station to undertake a test of these 

 different materials with the purpose of finding whether the dry materials 

 are effective, and how dilute the liquid concentrate may be used and still 

 be effective, for scale control. 



,\11 the materials used in the tests were of standard brands purchased 

 in the open market. A chemical analysis of each brand was made, as 

 shown in Table J. 



Table 1. Polysulfide sulfur and free sulfur in the materials tested. 



Polysulfide Free or Inert 



Sulfur, Sulfur, 



Per cent. Per cent. 



Lime-sulfur solution (33°+Beaume) 25-)- — 



Dry lime-sulfur 55-|- 6 



Sodium sulfur compound 41-)- 3 



Barium sulfur compound 21-)- 15 



The materials were u.sed at the strengths recommended by the manu- 

 facturers for scale control, and printed on the label or the container; 



