EXPERIMENT STATION BULLETINS. 



521 



POISONS USED IN SPRAYING. 



Eor Insects That Chew. 



ARSENATE OP LEAD. 



This poison is used very extensively. It can be secured for reason- 

 able fjrice, is ready to use at any time, does not easily injure the foliage 

 and is the only poison that can be safely used in the lime-sulphur sprays. 



It is usual 1}' sold in kegs or ''kits" or small barrels in the form 

 of a paste. Some companies have it in a powder form. This form 

 usually costs twice as much or more per pound as the paste form and 

 since it does not contain much water only one-half the amount in 

 weight should be used as is recommended for the paste form. 



A simple easy way to work the thick pasty arsenate of lead into a 

 thin smooth paste (as it should be before using either alone or in some- 

 thing) is to put the amount required in a keg; add water and churn 

 with a dasher. This is much quicker than to use a paddle. 



PARIS GREEN AND LIME. 



Always use lime with Paris green, it makes the poison stick better, 

 beside greatly reducing the danger of burning the foliage. 



For spraying from a barrel, the writer has found the following method 

 very useful, — Place from one-quarter to one-half pound of good lump 

 lime, or unslaked lime, in each of three or four tin pails which will 

 hold about three quarts or less. Old cans or crocks will answer just 

 as well. Add enough hot water to slake it into a thin cream or paste. 

 Now add to each lot, one-quarter pound of Paris green, previously 

 weighed out, and placed in paper bags, stir while the lime is hot and 

 allow to stand for some time. Now measure out about forty-four gallons 

 of water in your spraying barrel, and make a mark that will shoAv 

 how high it comes in the barrel, add the contents of one tin pail (viz., 

 one-quartor of a [tound of Paris green and one half pound of quick-lime 

 slaked) into the forty-four gallons of water in the barrel. Stir well and 



