June, 21'] HORSFALLS AND EYER: MILLIPEDE CONTROL 271 



1-100 gave distinct injuries as compared with the stand on a 

 check plot 2. Creosote oil, table II, when diluted 1 - 100, showed a 

 strong tonic action on the germination of the seeds. The same was 

 true on plot 30 on which sodium cyanide was used at the rate of 150 

 pounds to the acre. The reason for this was that the chemicals came 

 in direct contact with the seed. An examination of plots 3, 3a, 3b, 

 and 3c eight days after the several treatments were applied showed 

 that the siirface soil of the treated plots had become caked, thus pre- 

 venting the plants from breaking through the soil. A comparison of 

 these plots with their check, number 3, where the stand was already 

 showing, indicated the necessity of loosening the crust. The soil over 

 the seeds was raked by hand and an almost perfect stand resulted on 

 plot 3b, as shown in table II. 



Naphthaline flakes, either applied as a dust in the row, or mixed with 

 hydrated lime and broadcasted immediately before sowing, was a 

 check on the germination of the seeds. This treatment had a distinct 

 value as a repellent to the millipedes. The soil, however, where the 

 naphthaline was used, became dry. This condition was undoubtedly 

 a factor in low seed germination. Limed and unlimed check plots 

 provided comparisons with regard to this condition. Various other 

 materials were tested but these gave no control. 



Control by Poison Bait 



Spring Treatment:- In the spring of 1920, a tomato grower com- 

 plained that milHpedes were damaging seedlings under sash. The 

 pests were cutting the tomato seedlings at the surface and feeding on 

 a portion of the root system. Arrangements were made to test the 

 effectiveness of poison baits as usually recommended for these pests. 

 The various baits were scattered in handfuls over the surface of the 

 groimd between the plants and adjacent to the sides of the frames. 

 Observations showed that the millipedes fed upon all of the mixtures, 

 while attacks upon the tomato seedlings ceased. The most satisfac- 

 tory formula was composed as follows: 



Bran 2 pk. 



Molasses >^ - 1 pt. depending on quality. 



Sodiimi arsenite 2 oz. 



Water, in sufficient quantity to make mash. 



Fall Treatment:- In the auttmm of 1920, the above formula was 



again tried on lettuce beds under sash. The bait was scattered over 



the siirface of the soil in one series and in another test was placed either 



imder boards or in furrows along the edges of the cold frames, after- 



