13 



plat due to this old road, it will be seen that the real increase, if any, 

 due to the treatment would not have paid for its application. It did 

 not lengthen the period of blooming, increase the number of blooms, 

 or produce any marked increase in the yield. 



Field experiments at Mexia, — A field of li acres in the form of a 

 right-angled triangle was divided into a 1-acre plat for poisoning and 

 a one-half acre plat for check. On one side of the field, but separated 

 from it by a gully 20 3^ards wide, was another cotton field; the other 

 two sides were adjacent to a peach orchard and to farm buildings. 

 Beginning immediately after the first chopping an application of 

 Paris green of 1 pound per acre was made from a sack on each of 

 the following dates: May 16, 24, June 8, 29, July 8, August 4. From 

 July 30 to September 13 five examinations were made to determine 

 the relative number of squares infested on the poisoned plat and on 

 the check. 



Table III. — Examina(io)is of Paris-green experiment, Mexia, Tex. 



Plat. 



Paris green . 

 Check 



Paris green 

 Checli 



Paris green 

 Check 



Paris green , 

 Check 



Number 

 Date ex- |of squares 

 amined. exam- 

 ined. 



July 30 

 ....do... 



Aug. 9 I 

 ....do... 



Aug. IG 

 ....do... 



Aug. 29 

 ....do... 



Paris green Sept. 13 



Check do . . . 



134 



102 



Number 

 infested. 



125 

 94 



Per cent 

 infested. 



86.2 

 86.6 



85.7 

 86.4 



Number 

 of small 

 bolls ex- 

 amined. 



Number 

 of small 

 bolls in- 

 fested. 



100.0 

 100.0 



90.0 

 96.1 



93.1 

 92. 1 



Per cent 

 of small 

 bolls in- 

 fested. 



80.0 

 80.0 



83.8 

 86.3 



97.5 

 100.0 



100.0 

 100.0 



91.6 

 100.0 



An average of these five examinations shows that on the Paris-green 

 plat 01 per cent and on the check 92.2 per cent of the squares were 

 infested. The fact that the percentages are almost identical shows 

 that the poison had no effect, and this conclusion is borne out by the 

 yield. The poisoned plats produced 270 pounds of seed cotton, while 

 the check, which is only one-half the size of the poisoned area, gave 

 200 pounds, or an excess of 50 per cent over the poisoned area. 



Field experiments at Calvert. — An isolated 5-acre field was divided so 

 that one-half of it served as a check. The entire field was planted dur- 

 ing the third week in March, but growth was delayed by unfavorable 

 weather conditions. Beginning immediately after the first chopping. 

 May 26, applications of 1 pound of poison per acre were made every 

 seven days. Fifteen applications were made in all, the last being on 

 August 31. The cost of the poison used was $6.20 and the labor 

 .80, making a total of $17. The method of applying the poison 



211 



