6 THE HORN FLY OF CATTLE. 



REMEDIES. 

 The following notes on remedial measures are quoted from 

 Insect Life {Joe. cit.): 



Preventive Applications — Almost any greasy substance will keep 

 the flies away for several days. A number of experiments were tried in 

 the field with the result that train-oil alone, and train-oil with a little sul- 

 phur or carbolic acid added, will keep the flics away for from five to six 

 days, while, with a small proportion of carbolic acid, it will have a heal- 

 ing effect upon the sores which may have formed. Train-oil should not 

 cost more than 50 to 75 cents per gallon, and a gallon will anoint a num- 

 ber of animals. Common axle grease, costing ten cents per box, will 

 answer nearly as well, and this substance has been extensively and suc- 

 cessfully used by Mr. William Johnson, a large stock dealer at Warrenton, 

 Va. Tallow has also been used to a good advantage. The practice of 

 smearing the horns with pine or coal tar simply repels them from these 

 pests. Train-oil or fish-oil seems to be more lasting in its effects than any 

 other of the substances used. 



Applications to Destroy the Fly. — A great deal has been said dur- 

 ing the summer concerning the merits of a proprietary substance consist- 

 ing mainly of tobacco dust and creosote, known as "X. O. Dust," and 

 manufactured by a Baltimore firm, as an application to cattle, and it has 

 received an indorsement from Prof. J. B. Smith, entomologist of the New 

 Jersey Experiment Station. We are convinced that this substance has 

 considerable merit as an insecticide, and know from experience that it will 

 kill many of the flies when it touches them, although they die slowly, and 

 a few may recover. The substance costs 35 cents a pound, and is not 

 lasting in its effects. Where it is dusted through the hair, the flies on 

 alighting will not remain long enough to bite, but two days later, accord- 

 ing to our experience, they are again present in as great numbers as 

 before. A spray of kerosene emulsion directed upon a cow would kill the 

 flies quite as surely, and would be cheaper, but we do not advise an 

 attempt to reduce the number of these pests \>y actually killing the flies. 



How to Destroy the Early Stages. — Throwing a spadeful of lime 

 upon a cow-dung will destroy the larvte which are living in it, and as in 

 almost every pasture there are some one or two spots where the cattle 

 preferably congregate during the heat of the day, the dung which con- 

 tains most of the larvae will, consequently, be more or less together, and 

 easy to treat at once. If the evil should increase, therefore, it will pay a 

 stock-raiser to start a load of lime through his field occasionally, particu- 

 larly in May or June, as every larva killed then represents the death of 

 very many flies during August. We feel certain that this course will be 

 found in many cases practical and of great avail, and will often be of 

 great advantage to the pasture, besides. 



