INSECTICIDES. 13 



Rotation of crops is one of the readiest means of overcoming 

 or escaping insect attacks. Even small-fruit plantations 

 can be rotated to advantage. (See Chap. III.) 



Salt and lime wash. 25 pounds of lime (unslaked), 20 

 pounds of sulphur, 15 pounds of salt, 60 gallons of water. 

 To mix the above, take 10 pounds of lime, 20 pounds of 

 sulphur, and 20 gallons of water. Boil until the sulphur is 

 thoroughly dissolved. Take the remainder 15 pounds of 

 lime and 15 pounds of salt- slack and add enough of 

 water to make the whole 60 gallons. Strain, and spray on 

 the trees when milk-warm or somewhat warmer. This 

 can be applied when the foliage is off the tree, and will 

 have no injurious effects whatever on the fruit-buds or the 

 tree itself. For scale on deciduous trees in winter. (Cali- 

 fornian.) 



Snuff. Snuff may be used to kill plant-lice upon house-plants, 

 and in other places where fumigation or spraying cannot 

 be employed. Blow it lightly on the plants. See SULPHUR 

 AND SNUFF. 



Soap and arsenites. Soap, 4 pounds, which is dissolved in 

 1 gallon of hot water ; add 4 ounces of London purple or 

 Paris green, mix, and dilute with 50 gallons of hot water. 

 For various leaf -eating insects, but likely to injure tender 

 foliage, when the arsenite contains much soluble arsenic, 

 unless lime is added. 



Soap and lime wash. 5 pounds potash, 5 pounds lard 

 stirred in 5 gallons of boiling water; 1 peck quicklime 

 slaked in 5 gallons of boiling water, and mixed while hot 

 with the potash and lard mixture. Dilute by adding 2 

 gallons of boiling water for each gallon of the mixture. It 

 will keep indefinitely. Recommended for preventing the 

 attacks of borers, but, like all washes for this purpose, of 

 doubtful utility. 



Soap and soda wash. To soft soap add a strong solution of 

 common washing-soda, until the mixture becomes a thick 

 paint. Used for bark-lice and other scale-insects on the 

 dormant wood. 



