/^WING to the minuteness of red spiders and to the fact 

 ^that they live chiefly on the underside of the leaves 

 which they attack, they are comparatively little known to 

 the layman. 



Their infestation of cotton, cultivated violet, garden 

 bean, dahlia, sweet pea, and hollyhock gives much trouble 

 to farmers, gardeners, and housewives, but the result of 

 their work frequently is confused with " rusts." 



The red spider is known to feed on 183 kinds of plants, 

 of which 55 per cent are cultivated and 45 per cent are 

 native wild species. 



To prevent the spread of red spiders by eliminating 

 weeds about fields and by destroying the pest on door- 

 yard plants has been found possible, and as a control 

 measure is of first importance. 



By pulling and destroying the first few plants which 

 show infestation the pest often may be stamped out. 



Four different contact sprays have been found to be 

 entirely satisfactory for use against the red spider on 

 cotton. These are potassium sulphid, lime-sulphur, kero- 

 sene emulsion, and flour-paste solution, and the dilution 

 for each spray is given on page 13. Prevention is of vital 

 importance, however, owing to the heavy expenditure of 

 time, labor, and material which is necessary to control 

 the pest when it is abundant in fields. 



