﻿DEY SUBSTITUTES EOR LIQUID LIME-SULPHUE 



23 



Table 21. — Results of tests with dry barium-sulphur sprays against the San Jose 

 scale on apple trees at Bicknell, Ind., in 1922 



Material used 



Barium-sulphur No. 2. 



Do 



Do 



Liquid lime-sulphur i . 

 Check 



Quantity 



in 50 



gallons 



of spray 



Pounds 

 13 



19.5 

 26 



Gallons 



Hibernating scale 



Dead 



Per cent 

 72.1 

 81.9 



97.6 

 55.0 



Control 



Per cent 

 38.0 

 59.8 

 70.8 



94.7 



Infestation of young scale on 

 80 linear inches of new wood 

 (first generation) 



Number 

 of scales 



3,796 

 2,296 

 1,181 



175 



8,873 



Average 

 per inch 



47.45 

 28.70 

 14.76 



2.19 

 110. 91 



Percent- 

 age of 

 check 



42.8 

 25.9 

 13.3 



2.0 



J Baum§ 32.6°. 



The results given in Table 21 show that dry barium-sulphur, even 

 when used at the rate of 26 pounds to 50 gallons of water, did not 

 furnish a control of hibernating scale that could be considered effec- 

 tive, or one that approached the effectiveness of the liquid lime- 

 sulphur. If the value of the treatment is measured by the number 

 of young scales that settle on the new wood the same lack of control 

 is shown since 13 pounds to 50 gallons allowed almost half as many 

 young scales per inch as settled on the untreated check and over 21 

 times as many as were found in the liquid lime-sulphur plat. 



Even the maximum strength showed over six times as many young 

 scales as were present on the twigs sprayed with standard liquid lime- 

 sulphur. 



Table 22. — Results of tests with dry barium-sulphur sprays against the San Jose 

 scale on peach trees at Canton, Miss., in 1922 





Quan- 

 tity in 

 50 gal- 

 lons of 

 spray 



Hibernating 

 scale 



Infestation of young scale on 80 linear inches of 

 new wood 



Material used 



First generation 



Second generation 





Dead 



Con- 

 trol 



Num- 

 ber of 

 scales 



Aver- 

 age per 

 inch 



Per- 

 centage 

 of check 



Num- 

 ber of 

 scales 



Aver- 

 age per 

 inch 



Per- 

 centage 

 of check 



Barium-sulphur No. 2 



Liquid lime-3ulphur ' 



Check 



Lbs. 

 13.5 



Gals. 

 6.66 



Per cent 

 42.4 



77.6 

 20.2 



Per cent 

 27.8 



71.9 



343 



37 

 1,483 



4.29 



.46 

 18.50 



23.1 

 2.42 



573 



117 

 2,121 



7.16 



1.40 

 26.51 



27.0 

 5.5 









1 Baum6 32.6°. 



Only one strength of the dry barium-sulphur spray was used in 

 these experiments, and this failed to show an effective control when 

 either the hibernating scale or the young scale on new wood is con- 

 sidered. Although tlie liquid lime-sulphur gave rather poor control, 

 it was relatively much bettor than the dry material. 



