10 • FARMERS BULLETIN 856. 



times a single application at the proper time will suffice, although 

 two or three are required for the cabbage worm, potato beetle, and 

 certain other insects wdiich produce more than one generation an- 

 nually. 



LIME. 



Lime is used to control cabbage clubroot. It neutralizes soil acidity 

 and therefore tends to increase scab on potatoes. It acts at the same 

 time to a limited extent as a deterrent against certain insects which 

 may be in or on the soil, such as maggots and grubs, and is a good rem- 

 edy for slugs. xVir-slaked or hydrated lime is the best form to use. 



GAS LIME. 



Gas lime is particularly valuable against certain underground in- 

 sects. It may be placed between the rows of some crops, but as a gen- 

 eral rule should be used after the crop is off. It is a refuse or by-. 

 product of gas-manufacturing plants and is simply lime through 

 which the illuminating product has passed in the primary stage of 

 purification. It may be obtained frequently for the mere cost of 

 hauling. It is highly impregnated wdth gas and tarry substances 

 when perfectly fresh, giving out a strong odor for several days after 

 being applied. It should be remembered that it will kill plant life 

 as w^ell as insects, and it is best to use this on a small scale before 

 employing it extensivel3^ 



LIME-SULPHUR. 



Lime-sulphur is a valuable spray for fruit trees, but not suited foi- 

 use on vegetables. Experiments haA'e shown that potatoes are injured 

 rather than benefited by it. 



NICOTINE SULPHATE. 



For small garden plats 1 teaspoonful of nicotine sulphate should 

 be used to 1 gallon of water, to which a 1-inch cube of hard soap 

 should be added and thoroughly mixed. If a larger quantity is de- 

 sired, use 1 fluid ounce to 8 gallons of Avater, with the addition of one- 

 half pound of soap. Full directions are given on the covers of the 

 packages, and instructions accompany them. 



For large forms, like the pea aphis, the nicotine should be used 

 slightly stronger, and for small kinds, like the spinach ajihis, it may 

 be used considerably weaker. 



The following nicotine-spray formula will be found the best for 

 the average aphis or plant-louse on truck crops, as well as for tlirips: 



Nicotine sulphate (40 per cent) pint— f 



Soap (dissolved) pounds__ 2 



Water ^gallons 50 



This formula gives 1 part nicotine sulphate to 1,000 parts of water. 



The quantity of soap recjuired will vary with the quality of water, 



more soap being required in "hard" water; but on the average the 



