BULLETIN 'No. 201. 



POPULAR EDITION. 



INSECTICIDES AND FUNGICIDES 

 FOR FARM AND ORCHARD CROPS IN MASSA- 

 CHUSETTS. 



BY E.'B. HOLL.\ND, A. I. BOURNE AND P. J. ANDERSON. 



IXTRODrCTION. 



The insecticides and fungicides on the Massachusetts markets are sold 

 under the regulations of the national insecticide act of 1910. By this act 

 all materials of this kind must bear a guaranteed analysis. In the case of 

 Paris green and lead arsenate the law has established certain standards 

 of composition. In the case of other poisons containing arsenic, a regula- 

 tion made under the terms of the insecticide act specifies the form of 

 statement which must be made in the guaranty. For all other insecticidal 

 and fungicidal materials the guaranty may take one of two forms: — 



1. Either a statement of inert substances contained, that is, of materials 

 having no value in killing or repelling insects or in controUing fungous 

 diseases; or — 



2. A statement of the active ingredients contained, expressed in terms 

 of percentages, together with the percentage of the total inert ingredients. 



In practice, manufacturers of insecticides and fungicides almost uni- 

 versally guarantee the percentage of each active ingredient, together with 

 the percentage of the total inert substances present. 



While there is no indication that insecticides and fungicides as sold in 

 Massachusetts fail to live up to their guaranties, there is plenty of evi- 

 dence that purchasers of such articles fail oftentimes to interpret the 

 guaranties. This is particularly true in the case of articles for which 

 standards have not been defined by law. 



The complexity of the problem is truly marvelous. Arsenic has been 

 used in a variety of forms, — combined with lead, with lime, with zinc, 

 with copper; white, pink, gray or green in color; in paste, in heavy powder 

 or in bulky powder. Soaps in great variety are used. Emulsified oils are 

 in the market. Copper is used in a variety of concentrations; so also is 

 nicotine (tobacco). Sulfur in a variety of forms, with lime and without 

 lime, comes on the market. Then there is a great galaxy of commercial 



