Insects and IVeventives 



In fact, at the present time, I know of no method of fumigation, not in- 

 jurious to the plants, that will destroy the red spider. The fumes of sul- 

 phur seem to hold this insect in check, but unless sulphur is very carefully 

 used, the growing plants will be injured and often killed. The sulphur is 

 usually applied as a paint to the heating pipes, being either mixed with lime to 

 form a whitewash, or with linseed oil. It may also be mixed with the tobacco 

 extract, and when applied in this manner the combined fumes of the sulphur 

 and tobacco destroy the aphides, as well as check the spread of the red 

 spider. 



Red Spider 



Tetranychus himacalatus adult — Enlarged. 

 U. S. Dept. of Agriculture) 



{From Banks, 



Sulphur and Lime Formula. — Slack three pounds of quick lime in a 

 gallon of water, to which add one pound flour of sulphur, and stir till all is 

 evenly mixed. If the wash proves too stiff to be brushed on easily, add more 

 water. Paint three to four runs of pipe in each house. This paint should be 

 renewed about every eight or ten days. 



Sulphur and Linseed Oil Mixture. — One-quarter pound flour of sul- 



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