MAINE AGRICULTURAI, EXPKRIME;NT STATION, I9IO. 433 



Commercial concentrated lime-sulphur. During the past two 

 years several firms have placed on the market different brands 

 of concentrated lime-sulphur similar to the home-boiled article. 

 Quite a number of these have been tested experimentally and 

 as a rule these have given quite favorable results when com- 

 pared with the latter. While directions may be furnished with 

 the commercial brands, they should always be tested with the 

 hydrometer and the dilutions made on this basis, using the 

 table given above. 



"Variations in the degree of concentration of the commercial 

 lime-sulphur mixtures may occur with different barrels of the 

 same brand. Some companies compounding these sprays have 

 apparently not been able to produce a wash of definite strength 

 or have failed to realize the importance of maintaining a uni- 

 form grade for their product."* 



All other things being equal, an article testing rather high and 

 relatively free from sediment would be the more economical to 

 buy. Hydrometers do not detect soluble impurities added to 

 lime-sulphur concentrates for the purpose of increasing their 

 densities. The national law against the adulteration of fungi- 

 cides and insecticides will doubtless prevent this difficulty, but 

 if there is any reason to suspect the character of any brand of 

 goods a sample should be submitted to a chemical examination. 



Before buying any of these concentrated sprays the purchaser 

 should make sure that it is a lime-sulphur compound. At least 

 one other concentrated substitute for bordeaux the name of 

 which indicates that it is some sort of a soluble sulphur prepa- 

 ration has been known to produce disastrous results when ap- 

 plied to apple trees with arsenate of lead in even greater dilu- 

 tions than recommended by the manufacturers. 



FORMULAS FOR INSECTS WHICH CHEW. 



Formula 5. parts green. 



Paris green 3^ pound 



Lime (unslaked) 3 pounds 



Water 5° gallons 



The standard remedy for the destruction of insects which eat 



*Parrot, P. J., N. Y. Exp. Sta., Bui. 320, p. 423, IQOQ- 

 28 



