CHAPTER III 



MECHANICAL METHODS OF DESTROYING 

 INSECTS OR PREVENTING INJURY 



Many valuable mechanical methods of controlling insects are 

 employed, such as hand-picking, "bugging" or beating, collecting 

 in nets or in hopper-dozers, ditching, disking, driving and others. 



Hand-picking is useful for large conspicuous inactive insects, 

 such as the squash bug, potato beetle, cutworms and similar 

 caterpillars. It is one of the simplest measures that can be em- 

 ployed, and is valuable where other means cannot be used and 

 where labor is cheap. 



Bugging. — This term is often used for jarring and beating in- 

 sects from low plants into pans containing water and a thin 

 scum of kerosene. The water prevents the insect from es- 

 caping, and the floating kerosene kills every insect which comes 

 in contact with it. 



Collecting in nets. — Hand nets of muslin or cheese-cloth such 

 as school children employ for the capture of butterflies, are use- 

 ful against some insects which affect truck crops. Among such 

 are the tarnished plant-bug, which affects about equally vege- 

 tables and small fruits. By sweeping over the plants to be 

 protected and the weeds and grasses of the vicinity, thousands 

 can be captured in a short time, and they can then be killed by 

 throwing them into a fire or into hot water. 



Collecting in hopper-dozers. — Many forms of these death-deal- 

 ing devices are in use for grasshoppers (see figs. 2iy and 21^) 

 and for leaf-hoppers, which will be described in the discussion 

 of those insects. 

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