Sept. 3, 1917 



Quassia Extract as a Contact Insecticide 



513 



Table VII. — Methods of preparing spray solutions from quassia chips with various 

 solvents and results of preliminary tests of these solutions on tulip-tree aphids (Macro- 

 siphum liriodendri Mon.) in laboratory 



Experi- 

 ment 

 No. 



Object of methods. 



Effect of length of time of 

 maceration of chips. 



Effect of dilution of water 

 containing extract of 

 chips. 



Effect of repeated macera- 

 tion of chips. 



Effect of boiling and length 

 of time of boiling chips. 



Effect of diluting boiled wa- 

 ter containing extract of 

 chips. 



Effect of repeated boiling of 

 chips. 



Effect of maceration of chips 

 in soap solution and sub- 

 sequent boiling. 



Effect of diluting soap solu- 

 tion containing extract of 

 chips with water. 



Effect of diluting soap solu- 

 tion containing extract of 

 chips with soap solution. 



Effect of macerating chips in 

 I per cent sodium-carbon- 

 ate solution with subse- 

 quent boiling. 



Effect of macerating chips in 

 sodium - carbonate solu- 

 tions. 



Effect of macerating chips in 

 sodium - carbonate solu- 

 tion and then diluting 

 with water. 



Effect of macerating chips 

 in lye solutions 



Effect of macerating chips 

 in lye solution and then 

 dilutmg with water. 



Procedure. 



Length of time 

 of extractions, di- 

 lutions, number of 

 extractions, and 



strength of sol- 

 vents. 



25 gm. of chips macerated in 

 350 c. c. of water for: 



2$ gm. of chips macerated in 

 350 c. c. of water for 24 

 hours and diluted with 

 water. 



25 gm. of chips extracted 

 with 350 c. c. of water tor 2 

 hours; filtered and extrac- 

 tion repeated. 



25 gm. of chips boiled in 350 

 c. c. of water; evaporated 

 water replaced. 



25 gm- of chips boiled in 350 

 c. c. of water for 2 hours 

 under reflux condenser 

 and then diluted with 

 water. 



25 gm. of chips boiled in 350 

 c. c. of water for 2 hours; 

 filtered and process re- 

 peated. 



25 gm. of chips macerated for 

 24 hours in 3i;o c. c. of soap 

 solution and boiled for 2 

 hours. 



25 gm. of chips macerated in 

 350 c. c. of soap solution for 

 24 hours and diluted with 

 water. 



25 gm. of chips macerated in 

 350 c. c. of soap solution 

 for 24 hours and diluted 

 with soap solution. 



25 gm. of chips macerated in 

 350 c. c. I per cent sodium- 

 carbonate solution for 24 

 hours and then boiled for 

 2 hours. 



25 gm. of chips macerated 

 for 24 hours in s^;© c. c. of 

 sodium-carbonate solution 

 of the following strength: 



25 gm. of chips macerated 

 in 350 c. c. of 0.0; per cent 

 sodium-carbonate solution 

 for 24 hours and diluted 

 with water. 



25 gm. of chips macerated for 

 24 hours in 350 c. c. lye 

 solution of following 

 strength; 



25 gm. of chips macerated in 

 350 c. c. of 0.05 per cent lye 

 solution for 24 hours .ind 

 diluted with water. 



Num- 

 ber of 

 aphids 

 used. 



a) ^ hour 



b) I hour 



c) 3 hours 



d) 10 hours 



e) 48 hours 



a) Dilution i : K 

 6) Dilution i : J4 

 c) Dilution 1:1. 



a) First extraction 

 6) Secoadextrac- 

 tion. 



a) Boiled K hour . 

 6) Boiled i hour. 



c) Boiled a hours. 



d) Boiled 5 hours, 



a) Dilution i : J^, 

 6) Dilution 1:1.. 



c) Dilution 1:2. 



d) Dilution 1:4. 



a) First extraction 

 6) Second extrac- 

 tion. 



(o) No dilution... 

 (6) Dilution 1:2.. 



(c) Dilution 1:5.. 



(d) Dilution i ; 25. 



(a) Dilution 1:2. 



(b) Dilution 1:5. 



(c) Dilution i : 10 

 {d) Dilution i : 25. 



a) i.o per cent 



,6) 0.5 per cent. . . . 

 'c) 0.3 per cent. . . , 

 '4) o. I per cent ... 

 [e) 0.05 per cent. . . 



a) No dilution 



b) Dilution 1:5.. 



c) Dilution i ; 25 



a) o.; per cent. . . 



b) 0.3 per cent, .. 

 ,c) 0.1 per cent. . . 

 [d) 0.05 per cent.. 



a) No dilution... 



b) Dilution 1:5. 



c) Dilution i . 25 



283 

 92 

 164 

 1 28 

 32 



143 

 89 

 67 



34 

 37 



323 

 2Q4 



77 

 173 



131 



339 



230 



36 



Length 

 ot time 



re- 

 quired 

 to kill, 

 aphids. 



Hours. 



102 

 23 



64 

 IS 



With the exception of the effectiveness of the extract removed by the 

 sodium-carbonate solution, these results agree with those of the quanti- 

 tative determinations recorded in Table V. Furthermore, all of these 

 results closely agree with the statement made by Schmidt (39), who 

 4598°— 17 2 



