40 
soil to a depth of from 4 to 6 inches. The tobacco kills the aphi¢es 
by leaching through the soil, and acts for a year or so as a bar to 
reinfestation. The dust is a waste product of tobacco factories, costs 
about 1 cent per pound, and possesses the additional value of being 
worth fully its cost as a fertilizer. 
Since its early recommendation marked success has been reported 
from the use of tobacco dust. A notable instance is that given by 
Mr. M. B. Waite, of the Bureau of Plant Industry, who applied a 
ton of tobacco waste, costing $25, in his orchard, with the result of 
entirely renewing the vigor of his trees and producing a strong 
stubby growth of twigs. A peck of tobacco dust was placed about 
each of his larger trees in a circle of 2 or 3 feet around the trunk, 
and a slightly smaller amount about trees from one to three years 
old. 
KEROSENE EMULSION AND RESIN WASH. 
Kither the kerosene-and-soap emulsion or the resin wash, the 
former diluted fifteen times and the latter at the strength of the 
winter mixture, are used to saturate the soil about the affected plants 
and either left to be carried down by the action of rains or washed 
down to greater depths by subsequent waterings. 
For the grape phylloxera or the root-aphis of the peach or apple, 
make excavations 2 or 3 feet in diameter and 6 inches deep about the 
base of the plant and pour in 5 gallons of the wash. If not a rainy 
season, a few hours later wash down with 5 gallons of water and 
repeat with a like amount the day following. It is better, however, 
to make this treatment in the spring, when the more frequent rains 
will take the place of the waterings. 
For root-maggots enough of the wash is put at the base of the 
plant to wet the soil to a depth of 1 to 2 inches, preferably followed 
after an hour with a like amount of water. 
For white grubs in strawberry beds or in lawns the surface should 
be wetted with kerosene emulsion to a depth of 2 or 3 inches, follow- 
ing with copious waterings to be repeated for two or three days. The 
larvee go to deeper and deeper levels and eventually die. 
POTASH FERTILIZERS. 
For white grubs, wireworms, cutworms, corn root-worms, and like 
insects, on the authority of Prof. J. B. Smith, either kainit or the 
muriate of potash—the former being the better—are broadcasted in 
fertilizing quantities, preferably before or during a rain, so that the 
material is dissolved and carried into the soil at once. These not 
only act to destroy the larve in the soil, but are deterrents, and truck 
lands constantly fertilized with these substances are noticeably free 
from attacks of insects. This, in a measure, results from the in- 
creased vigor and greater resisting power of the plants, which of itself 
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