WINTER WORK IN GLASS HOUSES 



glass house which govern the growing of crops 

 in the field and garden in summer. Plants re- 

 quire an abundance of pure air, and one of the 

 most difficult things to learn will be just how 

 much air is required, when to open the ventila- 

 tors, and how to regulate the supply. Just a 

 word as to insects. It is not too much to say 

 that eternal vigilance is necessary here. These 

 small pests appreciate the joys of warm and 

 congenial surroundings, and will work as hard 

 as the gardener to take their toll ; it is only con- 

 stant watching and care that can keep them 

 in check. Tobacco stems, sulphur fumes, and 

 a sharp eye are the weapons necessary for the 

 conflict. 



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