XXXIX. SDMI" IXSECTvS AT Wr)RK OX FAKM 



CROPS 



"Thai ivhirh the palmencorm hath left hath the locust eaten; and that 

 which the locust hath left hath the cankenvorm eaten; and that which the 

 cankeru'orm hath left hath the caterpillar eaten. 



Awake, ye drunkard, and weep; and howl, all ye drinkers of wine, 

 because of the vew wine; for it is cut off from your mouth. 



For a nation is come up upon my land, strong, and without number, 

 whose teeth are the teeth of a lion, and he hath the cheek-teeth of a ^reat lion. 



lie hath laid my vine waste, and barked in y fig-tree; he hath made it 

 clean bare, and cast it away; the branches tJiereof are made white.'' 



—The Book of Joel, i :4-7. 



Before there were famis, the plants we cuki\'ate all had 

 their insect enemies. They developed together in the wild- 

 wood. The priniiti\'e farmer sotight out the valuable crop- 

 plants and brought them into his fields. The insects came 

 along with them, uninvited. 



The making of fields disturbed the nice balance of nature. 

 The massing together of plants that grew sparingly in the 

 wildwood, made it possible for their insect enemies to find 

 unusual food sup])lics, and to develop in extraordinary 

 numbers. Potato beetles, hatched in the garden, find food 

 plants waiting for them in ainmdancc; they do not ha\'e to 

 search the motmtain-sidc for a few straggling wild i)lants on 

 which to lay their eggs. Thus the fanner has made easier 

 conditions for them, and is himself responsible for their 

 unusual increase. It is because he has aided their increase 

 that he now must take measures for their destruction. 



Each kind of plant has its o\^^l insect enemies. Different 

 ones work in its leaf, its stem, its root or its fruit. No part is 

 exempt from attack. Some insects feed openly ujion tlie 

 plant; others are concealed, as stem-borers and leaf -miners. 

 Some, like the aphids, feed in great companies; others are 

 solitary. A few scale insects attach themselves to the bark 



