530 Bulletin 78. 



were found underneath the bark of the root in their burrows, while nearly 

 all the live maggots seen were on the lowest roots where perhaps the emulsion 

 had not penetrated. The puparia were replaced. June 7, both cages were 

 carefully examined. In the one examined May 30, 8 of the pupar.a were 

 still alive, but no live maggots were found. In the cage where the emulsion 

 WHS applied in a 50 part dilution, manv dead maggots, 12 dead and 12 ap- 

 parently live puparia, were found ; no live maggots remained. In similar 

 cages which received no treatment, from 71 to 95 puparia were found. The 

 killing power of the emulsion v\as thus very evident, and the 75 part dilution 

 seemed equally as effective as the 50 part. In fact, this emulsion gave the 

 most promising results of anything we tried here in the insectary, except the 

 bisulphide of carbon treatment described later. None of the plants showed 

 any injury from the application The same amount of the emulsion was ap- 

 plied to other plants, about large enough to set in the field, but which had 

 no insects on their roots ; and no injury had resulted from the applications 

 20 days later. 



Thus, our experience, both in the field and in the insectary, 

 lead us to believe that in this emulsion we have one of the cheap- 

 est, most effective, and most practicable killing agents that has 

 yet been suggested for combating these root maggots. The ma- 

 terial can be easily and cheaply obtained, so that the principal 

 expense is in its application. Always use the crude carbolic acid 

 as it is much cheaper than the purified and is nearly, if not quite, 

 as effective. It will probably be safer if used as an emulsion than 

 if simply diluted with water. We wotild advise that it be made 

 by the following formula : i lb. of hard soap or i qt. of soft soap 

 dissolv^ed in i gal. of boiling water, into which i pint of cnide 

 carbolic acid is then poured and the whole mass agitated into an 

 emulsion, which will remain in this condition for a long time. 

 In treating the plants, take one part of this standard emulsion 

 and dilute it with 30 equal parts of water ; it probably can be 

 used stronger without injury to the plants. If the emulsion is 

 cold and semi-solid use several parts of warm water at first. Be- 

 gin the treatment early, a day or two after the plants are up, or 

 in the case of cabbages and cauliflowers, the next day after they 

 are set in the field, and repeat it once each week or ten daj's until 

 about May 20 in our State. While we have little faith in the 

 preventive effects of the early treatments, we do believe that the 

 emulsion will then kill many of the eggs and recently hatched 

 maggots. If it could be applied with some force through a syringe 

 or force pump, it might not be necessary to go to this trouble of 



