INSECTICIDES. 109 



When biting insects attack plants which it is not 

 thought safe to poison, the use of a powder of air-slaked 

 lime or of dry wood ashes is often effective in discouraging 

 their attacks. Another repellant which sometimes works 

 like a charm is kerosene powder, made by stirring a table- 

 spoonful of the oil to a quart of pulverized gypsum, or air- 

 slaked lime, or even fine road dust. Scatter it on and 

 around the plant. 



Plants may also be often rendered unattractive to in- 

 sects by free sprinkling with tar water. Take a barrel 

 with a few gallons of gas tar in it, pour water on the tar, 

 and have it always ready when needed. When the insects 

 appear give them a liberal dose of the tar water from a 

 garden sprinkler or otherwise ; when the rain washes it 

 off the leaves, or the pests return repeat the dose. 



There are other biting and boring insects which destroy 

 plants by their injuries to the roots. Wireworms are a 

 conspicuous group of these destroyers. All underground 

 pests are naturally difficult of treatment and often in field 

 practice they cannot be economically destroyed or discour- 

 aged. In garden practice, however, the use of soot or ni- 

 trate of soda, in very small quantities, or of tobacco dust, 

 the extract of which is carried down by water to the dis- 

 comfiture of the pest, is often effective and profitable. 



Another group of biting pests though not strictly in- 

 sects, are slugs and snails. They can be poisoned by the 

 use of poisoned leaves laid on the ground, or they can be 

 trapped either with leaves or pieces of board or little piles 

 of wheat bran. Early in the morning the slugs will be 

 found in large numbers under the leaves or boards, or 

 collected in the bran, and can easily be gathered up for 

 breakfast in the poultry yard. Mother hens in portable 

 coops with the young chicks or ducks running among the 

 plants, are a very good solution of the slug question on a 

 small scale. Myriads of slugs in the garden are often due 

 to excessive irrigation. If the surface is finely worked up 



