﻿DRY SUBSTITUTES FOE LIQUID UME-SULPHUR 3 



a spray, but the proper application of most of the materials listed 

 gave good control." 



In 1923 {15, p. 2) it is stated: 



During the past three years most growers in this State have controlled the 

 scale with lime-sulphur, though some have lost faith in it. Dry lime-sulphur 

 preparations have failed in our experiments to give satisfactory control. 



The New Mexico station in its annual report for 1918-19 {12, 

 p. 15) says: 



5. San Jose scale. — Dry lime-sulphur and concentrated lime-sulphur were used 

 as sprays for the above scale. The dry lime-sulphur dissolves readily, v/ith little 

 or no residue, is much more easily prepared, saves time, and is just as effective. 

 Many of the chemical spray companies think the prices will be so reduced in 

 another year that every farmer and orchardist will be able to use it. Between 

 the two above sprays, the dry lime-sulphur is the coming insecticide for the San 

 Jose scale. 



In the report of the New York station for 1923 {20, p. 4^) is found 

 the following statement : 



In this season's efforts provision was made for tests of various commercial 

 sulphides in a powdered or granular state in comparison with lime-sulphur solution 

 at standard strength. On the basis of the initial killing of the San Jose scale 

 on old apple trees, the dry sulphides were noticeably inferior to lime-sulphur, while 

 oil emulsions gave better control of the pest than lime-sulphur. 



In the monthly bulletin of the Ohio station for February, 1920 

 (16, pp. 50-51), tests are reported with one calcium-sulphur, one 

 sodium-sulphur, and one barium-sulphur, and it is stated that ''com- 

 mercial or practical control" was obtained. 



In a later issue {1, p. 25) the following statement is made: 



The powdered lime-sulphur has not yet been sufficiently tested to warrant us 

 in recommending it as a perfect substitute for the liquid lime-sulphur, but we 

 have cleaned an orchard badly encrusted with San Jose scale by applying it 

 in the spring, 12 pounds to 50 gallons of water. * * * Until more extensively 

 tested we do not recommend it as being so reliable for cleaning badly infested 

 orchards as liquid lime-sulphur or iniscible oil, but believe it can be safely used 

 for a few seasons, at least, as a dormant spray in orchards only slightly or not 

 at all infested with scale. For dormant use, mix 15 pounds with 50 gallons of 

 water. 



The Oregon station in 1924 {21, p. 8) states that barium-sulphur 

 "has been shown to be a fairly effective contact poison, but it possesses 

 no distinct advantage over the lime-sulphur solution except that it is 

 in powder form and convenient to handle," and sodium-sulphur ''is 

 similar to lime-sulphur except that lye is used instead of lime in its 

 preparation. As a dormant spray it has been found satisfactory, but 

 it has no superiority over the lime-sulphur." 



In reference to calcium-sulphur this bulletin says: 



When dry lime-sulphur is used either for the dormant spray or for the summer 

 sprays it should be applied in amounts e(|uivalcnt to the liquid lime-sulphur in 

 order to obtain equivalent protecti(jn. Since each gallon of lime-sulphur solution 

 contains .3.4 pounds of active ingredients it would take 4 pounds of a dry lime- 

 sulphur having 85 per cent active ingredients to be equivalent to 1 gallon of liquid 

 lime-sulphur. Therefore, in making dilutions for the various sprays 4 pounds of 

 the dry lime-sulphur should be used for each gallon of lif)uid lime-sulphur, Baumd 

 '•^'i° , necessary. While this amount is much higher than is recommended by the 

 manufacturer, field experiments carried on in different parts of the country have 

 indicated conclusively the need of using larger amounts than the manufacturers 

 have recommended in the past, particularly when weather conditions favor the 

 development of serious disease epidemics. 



