308 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 7 



check were as in the first series but no seed was planted on the date of 

 soil treatment. The treatment with cyanide in this series was on 

 Maj' 29. On June 10 one pot from each of the four groups in the series 

 was seeded. On June 24 a second pot from each group was seeded and 

 on Jul}' 8 the remaining pot in each group was seeded. The third 

 series of twelve pots (Division C) was entirely seeded on May 29 but 

 no cyanide treatment was made at the time of seeding. The first 

 group of three pots was never treated with cyanide and, as in series 

 A and B, served as a check. The second group was treated with cya- 

 nide, June 10, the same amounts being used as in the other series. The 

 third group was similarly treated on June 24 and the fourth group was 

 similarly treated on July 8. The accompanying tables are self-exjDlan- 

 atory. The experiments showed conclusively that sodium cyanide 

 cannot be placed in the soil at the time of seeding with the fertihzer 

 and cannot be placed in the soil during the process of cultivation sub- 

 sequent to seeding. These experiments also show that sodium cya- 

 nide is decreasingly poisonous up to from twenty-six to forty days after 

 application, after which no appreciable difference can be found between 

 treated pots and untreated checks, thus setting a margin of danger 

 in seeding, after treatment with this fumigant, of forty days. 



As laboratory results are always subject to discrepancies, due to 

 necessarily artificial conditions, two field exiDeriments were conducted 

 at Wolfville, Md., and a third at Bridgeport, N. Y. The two field 

 experiments, at Wolfville, Md., were conducted during the month of 

 June. In one field cyanide, at the rate of about 300 pounds per 

 acre, was drilled into the corn hills by hand, simulating, as near as 

 possible, the depth and distance from the plants that it would be if 

 drilled in by machinery when cultivating the crop. The corn in this 

 field was planted on May 13 and the plants were about ten inches tall 

 when treated on June 6. Sixty-seven hills were treated. The field 

 was again visited on June 18 and on that date every treated hill was 

 killed out, the plants being dried up. In another field cyanide was 

 applied at the rate of about 150 pounds per acre in the same manner as 

 the above and when again examined on June 18 gave the same results. 



The field experiments at Bridgeport, N. Y., come under two h-eadings, 

 to answer the first and third phases of remedial measures as outlined 

 in the third paragraph of this paper. Wireworms (Agriotes mancus) 

 were in the fields in enormous numbers, in fact so numerous that 

 application was made to our office for assistance. Corn was so badly 

 infested that some fields were reseeded while all were ''planted in" 

 as a result of the depredations of these insects. The general practice 

 on the farms in this region, which are principally hay farms, is to keep 

 land in sod for three. years at least and, if it is still" producing a fair 



