88 VEGETABLE GARDENING 



are: (i) It is harmless to the foliage, (2) it adheres better 

 to the foliage; (3) it remains longer in suspension. The 

 usual strength is 3 pounds of lead arsenate to 50 gallons 

 of water. Weaker mixtures are often effective, while 5 

 pounds to 50 gallons may be an advantage in killing in- 

 sects difficult to poison. The commercial preparation 

 which comes in the form of a paste should be mixed thor- 

 oughly with a small quantity of water before diluting in 

 the sprayer. It may be used with bordeaux mixture 

 without diminishing the value of either. 



130. Paris green, a stomach poison which has been 

 used extensively for many years in combating chewing 

 insects. In order to prevent injury to foliage, it is always 

 desirable to add some lime in the preparation of the 

 spray. One pound of lime and one pound of paris green 

 are used with 75. to 200 gallons of water, depending upon 

 the susceptibility of the foliage to burning. It is always 

 safer to have a slight excess of lime in the mixture. The 

 paris green becomes more thoroughly diffused in the 

 water if it is first mixed to a paste. As it is simply held 

 in suspension and as it sinks quickly, the spray pump 

 should be provided with an agitator to keep the mixture 

 constantly stirred while being applied. 



131. Hellebore. White hellebore finds favor among 

 some home gardeners mainly because it soon loses its 

 poisonous principle when exposed to the air. As a stom- 

 ach poison it is effective for cabbage worms and other 

 pests, if the material is fresh when applied. It may be 

 used as a powder, but the distribution is more thorough 

 if applied as a spray, using y 2 to 2 ounces of powder in 

 2 gallons of water. 



132. Kerosene emulsion is probably the most exten- 

 sively used of contact poisons for sucking insects. It is 

 prepared as follows : Dissolve J^ pound of hard, soft or 

 whale-oil soap in a gallon of hot water ; while hot, add 2 

 gallons of kerosene. Then use a force pump provided 



