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the roots of the white hellebore, and kills both by contact and by 

 being eaten. Very effective when fresh, it loses its strength by 

 standing. In doses loz. to three gallons of water it is much used 

 against the pear slug and leaf-eating worms. 



Pyrethrum, or Insectibane, is also a poison, and is effective 

 when fresh, but loses strength when exposed to the air. It is made 

 from the powdered flowers of plants of the genus Pyrethrum. That 

 light-brown powder is dusted over the plants or sprayed, in the pro- 

 portion of Pyrethrum one tablespoonful, boiling water two gallons. 

 It kills by contact, and should be applied as long as the insects 

 persist. Burnt over hot coals in the conservatories and greenhouses, 

 it rids plants of aphis and other insect pests. Pyrethum are easily 

 cultivated, make pretty borders, and a supply of fresh flowers could, 

 without trouble, be raised in every garden. 



Kerosene, in the form of an emulsion with soapsuds, or 

 mechanically mixed with water in the form of a misty spray, in the 

 proportion of one of kerosene and four of water, will kill nearly all 

 insects, and not injure the foliage. 



Resin Compound is known to be very effective against scale 

 insects. One of the best formulas is : caustic soda, one pound ; 

 resin, five pounds ; water, 25 gallons. Two ounces of Paris green 

 may be added to this when used. 



Sal Ammoniac (chloride of ammonia) at the rate of f to loz. 

 per gallon of water, is a cheap and efficacious spray against red 

 scale. 



Tobacco is one of the safest and most valuable insecticides, 

 and may be applied in several ways ; either as a fine dry powder 

 against slugs and aphis, or as a decoction of three to four gallons 

 of water to one pound of tobacco ; or in fumes, when burnt in the 

 greenhouse. 



Carbolic Acid, especially in its crude state, is a valuable 

 insecticide as an emulsion made by mixing one quart soft soap, or 

 about one pound of hard soap dissolved in two gallons of boiling 

 water, and then adding one pound crude carbolic acid ; and, applied 

 with a cloth or a brush, it is efficacious in preventing the attack of 

 tree borers. It must not, in that state, be applied to the foliage. 



Bi- Sulphide of Carbon, a very volatile fluid, the fumes of 

 which are destructive to all animal life, is used for killing insects 

 underground ; this is done when the plant is dormant, by boring a 

 hole into the ground and pouring in a little carbon bi-sulphide and 

 kerosene mixed. It is highly inflammable. 



Coal Tar is excellent to drive insects away, or entrap them. 



Hot Water, at a temperature of about 125 deg. F., is very 

 efficacious for killing plant lice. Amongst other substances which 

 are used against insects must also be mentioned lime and gas lime, 

 quassia chips, kainit, fir-tree oil, sulphate of copper. 



