ARSENirE OF SODA A SUBSTITUTE FOR PARIS 



GREEN. 



HE Ohio Experimental 

 Station at Worcester, has 

 published a bulletin ad- 

 vising the use of soluble 

 arsenic in place of Paris 

 green. As shown in the following selec- 

 tion, Paris green is a good insecticide, 

 but is somewhat troublesome to use in 

 liquid form, as it does not dissolve read- 

 ily, and needs constant agitation to keep 

 it from settling. 



If allowed to settle at all the dis- 

 tribution is not uniform, and injury is 

 likely to result to the foliage of some 

 plants, while the insects on other plants 

 escape. Moreover, it is unduly expen- 

 sive, whether used dry or in the form of 

 a spray. 



White arsenic, in soluble form, costs 

 about one-third as much as Paris green 

 and gives no trouble in the way of set- 

 tling. 



Dissolve two pounds of commercial 

 white arsenic and four pounds of car- 

 , bonate of soda (washing soda) in two 

 gallons of water and use one and one- 

 half pints to a barrel of Bordeaux mix- 

 ture (50 gallons). 



The easiest way to make the solution 

 is to put both the white arsenic and car- 

 bonate of soda in a gallon of boiling 

 water and keep boiling about fifteen 

 minutes, or until a clear liquid is formed, 

 and then dilute to two gallons. 



One and one-half pints of this. solu- 

 tion to each barrel of Bordeaux mixture 

 is sufificient to use when spraying for 

 potato blight and potato bugs, for apple 

 scab and apple worms, or for any other 

 purpose where a combination mixture 

 for fungi and insects is required. 



This combination has been fully 

 tested at the Ohio Experiment Station 



and found to be quite as effective as the 

 Paris green and Bordeaux mixture com- 

 bination, and for the reasons given 

 above is much to be preferred 



This arsenic and soda solution, or 

 arsenite of soda, is more safely used in 

 combination with Bordeaux mixture 

 than alone, as when in combination it 

 will not injure the foliage, but alone it 

 is liable to burn the leaves. The same 

 objection holds good, however, with 

 reference to Paris green and London 

 purple. 



It is better, however, in almost every 

 case, to use the combination mixture as 

 fungi are nearly* always present and 

 unless they are kept in check there is 

 but little use of fighting insects. 



Specific directions for making and 

 using Bordeaux mixture, as well as 

 how to control various insect pests, can 

 be found in a spray calendar issued by 

 the Ohio Experiment Station. 



The arsenite of soda may be prepared 

 in any quantity desired, but being al- 

 most a clear liquid is somewhat danger- 

 ous to keep on hand. The danger may 

 be obviated, to some extent, by color- 

 ing the liquid with some cheap aniline 

 dye, using enough of the latter simply 

 to give sufficient color so that no one 

 would mistake the solution for an in- 

 offensive drink. 



It takes but a short time, however, to 

 prepare sufficient for a day's spraying, 

 which is, perhaps, the least dangerous 

 method. It is a rank poison and should 

 be properly labeled and carefully 

 guarded, the same as all other poisons. 

 Insects may be the means of spreading 

 fungous diseases and fungi may so en- 

 feeble plants as to make them an easy 

 prey to insects. 



