16 
cents to 4 cents a pound, making the mixture cost, as applied to the 
trees, from 7 cents to 8 cents a gallon. 
PYRETHRUM, OR INSECT POWDER. 
This insecticide is sold under the names of Buhach, Dalmatian, and 
Persian insect powder, or simply insect powder, and is the ground-up 
flowers of the Pyrethrum plant. It acts on insects externally through 
their breathing pores, and is fatal to many forms both of biting and 
sucking insects. It is not poisonous to man or the higher animals, 
and hence may be used where poisons would. be objectionable. Its 
chief value is against household pests, such as roaches, flies, and ants, 
and in greenhouses, conservatories, and small gardens, where the use 
of arsenical poisons would be inadvisable. 
Tt is used as a dry powder, pure or mixed with flour, in which form 
it may be puffed about rooms or over plants. On the latter it is 
preferably applied in the evening, so as to be retained by the dew. To 
keep out mosquitoes, and also to kill them, burning the powder in a 
tent or room will give satisfactory results. 
It may also be used as a spray at the rate of 1 ounce to 2 gallons of 
water, but in this case should be mixed some twenty-four hours before 
being applied. For immediate use, a decoction may be prepared by 
boiling in water from five to ten minutes. 
TOBACCO DECOCTION. 
A tobacco decoction sufficiently strong for aphides and other very 
delicate insects may be prepared from tobacco stems and other refuse 
tobacco by boiling at the rate of 1 pound for each 1 or 2 gallons of 
water, sufficient water being added to make up for that lost in boiling. 
SULPHUR. 
Flowers of sulphur is one of the best remedies for plant mites, such 
as the red spider, the six-spotted orange mite, and the rust mite of 
citrus fruits. It may be applied in several forms, the simplest of 
which is its use as a dry powder dusted over the trees with powder 
bellows or any broadcasting device, preferably in the early morning 
when the foliage is damp with dew, or immediately after a rain. For 
the rust mite in very moist climates, such as that of Florida, to keep 
the fruit bright it is sufficient merely to sprinkle the sulphur about 
under the trees. The flowers of sulphur may be easily applied also 
with any other insecticide, such as kerosene emulsion, resin wash, or 
a soap wash, mixing it up first into a paste and then adding it to the 
spray tank at a rate of from 1 to 2 pounds to 50 gallons. 
Somewhat more uniform results can be obtained perhaps by getting 
the sulphur into solution, either dissolving it with lye or by boiling 
it with lime. 
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