32 
THE COLORADO EXPERIMENT STATION 
divided that it settles slowly, and consequently can be more evenly 
distributed than most arsenical mixtures. Its third point of su¬ 
periority is in its adhesive qualities when applied to foliage. Appli¬ 
cations made to foliage in the latter part of May at this Station could 
plainly be seen upon the leaves the first of September. The dis¬ 
advantage of the poison is its not being quite so quick to kill the 
insects that eat it as are the other arsenites, consequently it is 
necessary to use it in stronger mixtures. 
To prepare arsenate of lead, dissolve in water arsenate of soda 
and acetate of lead (white sugar of lead) in the portion of three 
pounds of the former to seven pounds of the latter. Then use not 
less than five or six pounds of the combined chemicals to each 
hundred gallons of water. Three or four times this strength will 
do no harm to foliage. If the poison is purchased ready made, 
use: 
Arsenate of lead.4 to 6 pounds 
Water.100 gallons 
6. ARSENITE OF LIME. 
White arsenic and lime may be made to combine, forming an 
arsenite of lime that is practically insoluablein water. The poison 
may be prepared in either of two ways. What is known as the 
Kedzie formula is as follows: 
“Boil two pounds of white arsenic and eight pounds 
of salsoda for fifteen minutes in two gallons of water. 
Put into a jug and label * poison ’ and lock it up. 
When ready to spray, slack two pounds of lime and 
stir it into forty gallons of water, adding a pint of the 
mixture from the jug. 
The other method is to boil together arsenic, lime and water 
for a full half hour in the following proportions: 
White arsenic.1 pound 
Lump lime.4 pounds 
Water. . 4 gallons 
Then dilute to 200 gallons of water before applying to foliage. 
These preparations have become very popular in the past few 
years and deservedly so. White arsenic is cheap and consequently" 
is in very little danger of adulteration, so that one is almost certain 
of the strength of his mixture when using this poison. Care must 
be taken, however, to use fresh unslacked lime of good quality. 
Before being diluted for use, the mixture should be passed 
through a coarse cloth or seive, to take out the lumps that would 
otherwise clog the spraying nozzle. 
