CIVILIZATION AND INSECTS SMITH 265 



The honeybee is not a native North American insect, but was 

 introduced by the early, thrifty colonists to function as one of the 

 earliest factories on the continent. It is estimated that there were 

 4,620,650 colonies of bees in the United States in 1931 and that these 

 colonies produced about 160,000,000 pounds of honey.^*' This is an 

 industry of no mean proportions. The honeybee has remained un- 

 changed by centuries of domesticity, but its effect on civilization is 

 measurable. In addition to the production of honey and wax, these 

 creatures are receiving increased recognition as pollenizers of or- 

 chards. The late increase in the acreage of sweetclover has pro- 

 vided them with an additional excellent source of nectar. 



LIMITATIONS PROVIDED BY CIVILIZATION 



Insects do not have complete freedom in their spread. Man has 

 set up various mechanical and artificial barriers which are more or 

 less effective to their invasions. One thinks at once of the many 

 quarantines enacted and promulgated to keep out undesirable foreign 

 pests and to prevent or check the spread of those already introduced. 

 Examples are too familiar to repeat. 



The range and abundance of the Texas fever tick is being reduced 

 markedly in the southern States. Large areas are now tick-free, 

 owing to the persistent prosecution of a systematic program of tick 

 eradication. 



Man is the insect's worst enemy. He destroys them by barrages of 

 poison gas, with poisoned food, and with merciless mechanical de- 

 vices which trap them, crush them, or keep them out of the most 

 attractive places. He burns them, scalds them, freezes them, starves 

 them, or drowns them. Furthermore, he gives aid and comfort to 

 their other enemies, such as their parasites, predators, and diseases. 

 But where in the animal kingdom is such tenacity and persistence 

 displayed as in insects ? It is truly the battle of the centuries. 



Finally, the competition offered by insects to civilized man has 

 forced him to be a better farmer and citizen. This point should be 

 mentioned in a low tone of voice because inborn prejudices regarding 

 the joy of work make this a difficult point to evaluate. Nevertheless, 

 plowing under the wheat stubble promptly after harvest to destroy 

 the Hessian fly puparia has resulted in better seed-bed preparation 

 for the next crop, while the fly-free planting dates in many commu- 

 nities are very near to or coincide exactly with the planting date for 

 maximum yields. The mosaic disease carried by the corn leaf or 

 sugarcane aphid (Aph/'s mmdis) so seriously damages native vari- 

 eties of sugarcane in the West Indies that mosaic resistant varieties 



"Olsen, Nils A. Estimated colonies and yield of honey by states, 1928, 1929, 1930, 

 and 1931. U. S. Dep. Agr. Bur. Agr. Econ. Mimeogr. leaflet, Nov. 15, 1932. 



