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The soluble arsenic in Paris green, or in any arsenical 

 insecticide, is liable to injure the foliage of the plants to 

 which it is applied ; and it has been found that when the 

 percentage of this is more than the proportion already 

 mentioned considerable injury to plants is likely to 

 result. 



Paris green may be used either as a spray in a mix- 

 ture with water, or dry. When applied dry it may be 

 employed by itself or mixed with lime or any other dry fine 

 powder. If it is used as a spray, the Paris green mixture 

 should be applied by means of a very fine nozzle attached 

 to a fairly strong force pump. When used dry, it should 

 be very evenly distributed over the surface of the plant 

 in such a way that all parts are reached by it, and at the 

 same time, so that there is no thick layer of this substance 

 on any part of the plant. It has been found in practice, in 

 the West Indies, that Paris green is best applied as a dry 

 mixture with finely pulverized air-slaked lime, the 

 mixture being at the rate of 1 Ib. of Paris green to 5 or 6 Ib. 

 of lime. The same proportion will be maintained if the 

 mixture is made by using one part in bulk of Paris green to 

 ten or twelve parts of dry air-slaked lime. 



Several mechanical devices are available for the applica- 

 tion of dry Paris green, some of which will be found under 

 the heading of The Application of Insecticides. For use in 

 cotton fields, and in connexion with similar low-growing 

 crops in the West Indies, it has been found that cloth bags 

 of fairly fine mesh are very satisfactory for the distribution 

 of Paris green. 



Paris green is useful in combating a great variety of 

 insects which have biting mouth parts. It has been most 

 used in the West Indies in dealing with the cotton worm ; 

 but in other parts of the world it has been employed 

 against nearly all kinds of leaf-eating caterpillars, grasshop- 

 pers and cut worms. 



Paris green is used as follows : 



As a spray. 1 Ib. to 150 to 200 gallons of water. Mix 

 the Paris green to a paste in a small amount of water before 

 making up to the full quantity. Add 2 Ib. of freshly slaked 

 lime to each pound of Paris green. Apply by means of a force, 

 pump, using a nozzle which gives a very fine spray. 



As a dust or powder. Mix Paris green and dry air- 

 slaked lime in the proportion of 1 Ib. of the former to 5 or 6 Ib. 



