512 



A review of published reports of comparative tests of sprays made 

 from lime-sulphur solution, dry lime-sulphur, dry soda-sulphur and 

 dry barium sulphur are given. Comparative spraying tests were carried 

 out on Aspidiotits pcrniciosus (San Jose scale) at Washington in 1917 

 and 1918, in which the dry form compared favourably with the liquid. 

 Excellent results are reported from Illinois with 151b. dry lime-sulphur 

 to 50 U.S. gals, water, and 12i- lb. soda-sulphur to 50 U.S. gals, water, 

 and fair to good results from 14 lb. barium sulphur to 50 U.S. gals, 

 water, while the results from a commercial solution said to contain 

 double the amount of active sulphur were only rated as good. The result 

 of experiments in New Jersey on Aphid eggs are given [R. A.E., A, viii, 

 30]. The following sprays were tested on the eggs of Bryohia praetiosa : 

 Concentrated commercial lime-sulphur solution diluted 1 in 8, 1 in 10, 

 1 in 12 and 1 in 15 ; 13 lb. and 6h lb. barium sulphur to 50 U.S. gals. 

 water ; 6 lb., 10 lb. and 15 lb. dry lime-sulphur to 50 U.S. gals, water. 

 A hundred per cent, kill was recorded from all lime-sulphur solutions. 



From comparative tests on rust mites in Florida it was concluded that 

 dry sulphur compounds used on the basis of their sulphur content 

 give satisfactory results in controlling this pest. In tests where the 

 sulphur in solution was less than that contained in lime-sulphur solution, 

 the latter was superior. Future experiment may show that these can 

 be used slightly under the sulphur content basis. 



Though the question has not been settled, the author considers 

 from the evidence collected, that practically the same results will be 

 produced from the application of the same sulphur compounds whether 

 purchased in solution, as the commercial 33° Be. hme-sulphur solution, 

 or as dry powder. Experiments to prove this contention will not be 

 convincing unless the composition of the actual materials under test 

 is known. A few instances are given of how the composition may 

 change and deteriorate. 



De Oxg (E. R.). Suggestions for the Control of Red Spiders in 

 Deciduous Orchards. — Mihlv. Bull. Cal. Dept. Agric, Sacra- 

 mento, X, nos. 5-6, May-June "1921, pp. 186-191, 2 figs. 



The common red spider {Tctranychiis tclariiis, L.) hibernates in 

 the adult and nymphal stages among leaves and in the soil. In sheltered 

 places the mites may feed on hardy plants such as Convolvidtis arvensis 

 and Malva parviflora. They migrate in spring to orchard trees and 

 other plants, feeding on the lower surface of the leaf, where also the 

 eggs are laid. 



Remedial measures recommended are the destruction of winter- 

 growing weeds before they mature in order to delay infestation. Peas, 

 vetches and grain crops seldom harbour this pest, and should be culti- 

 vated where possible. The trees should be irrigated before any signs 

 of drought. Where the pest is common, sulphur in liquid or dry form 

 should be applied when the attack usually begins, this being the end 

 of June and early July in Sacramento. A liquid spray is more satis- 

 factory, as one thorough application is enough. It can be made 

 by mixing dry sulphur with glue water or flour paste, or by 

 using sulphur pastes or wettable sulphurs. About 5 lb. sulphur 

 should be used to every 100 U.S. gals, spray mixture. The sulphur- 

 glue mixture consists of 51b. sulphur (flowers or sublimed), f oz. dry 

 glue dissolved in \\ U.S. gals, hot water, and 100 U.S. gals, water. 

 The sulphur and glue water mixed into a paste should be rubbed through 

 a sieve into the spray tank. Flour paste may be substituted for glue 



