CHAPTER XIV 



INSECTS INJURIOUS TO MINOR VEGETABLE CROPS 



The crops treated in this chapter — rhubarb, okra, salsify, 

 pepper, water-cress and lettuce — are not, as a rule, seriously 

 injured by insects and the control of these pests is of less im- 

 portance in the culture of these vegetables than in the case of 

 those previously treated. 



Rhubarb 



Rhubarb is not usually seriously affected by insects. Its 

 most important enemies are the rhubarb curculio, the hop 

 flea-beetle, the spinach aphis, the bean aphis and certain species 

 of cutworms. 



The rhubarb curculio, Lixus concavus Say 



The leaf-stalks of rhubarb are often injured by the feeding and 

 egg-laying punctures of a rather large black, yellow-dusted 

 snout-beetle. The sap exudes from the wounds and collects 

 as glistening drops of gum. Fortunately the eggs' do not hatch 

 when deposited in rhubarb but are killed by the flow of sap. 

 This insect ranges from New England to Idaho and southward 

 to Florida and Louisiana. 



The beetle (Fig. 151) is about i inch in length and black in 

 color dusted with a yellowish covering which easily rubs off. 

 The head is provided with a curved snout on the end of which 



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