equally well to the use of the kerosene emulsions. In the case of 

 other plants thorough experiments are still necessary, and all insecti- 

 cides should be first used in comparatively high dilution. In general 

 it may be said that tender, young foliage is more susceptible and 

 must be carefully treated. Thin-leaved, pilose plants are more 

 readily injured, while thick-leaved glabrous species are least affected. 

 Annual plants, such as cabbages and other garden vegetables, are 

 more susceptible than perennials, but in the case of root crops, such 

 as beets, turnips, radishes, and potatoes, there is not the same need 

 of caution as to damage to foliage. Damage to foliage is not shown at 

 once, and in case of rain following an application another application 

 should not be made for several days. Fruit trees should not be 

 sprayed with arsenical poison before the blossoms fall, on account of 

 the danger of poisoning honey bees. 



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