SURVEY QUESTIONS 



What do we mean by economic value ? What plants have the greatest 

 economic value in your locality ? Why are birds called the farmer's best 

 friends ? How can you conserve bird life in your community ? What crops 

 are damaged by insects ? How are insect pests controlled ? 



Ewing Galloway 



UNIT XVI 



HOW DOES MAN CONTROL HIS ENVIRONMENT FOR 



WEALTH? 



Preview. To the boy or the girl living in the city green plants 

 seem to have little direct value. Although we see vegetables for 

 sale in stores, and we know that fruits have a money value, we are 

 not likely to realize that the wealth of our nations depends upon 

 growing crops more than it does on manufactories and business 

 houses. The economic or " dollars and cents " value of plants is 

 enormous, and our lives depend on the food which they supply. 



Another great source of wealth is the animals man uses for food, 

 as a source of raw material for clothing, furs, dyes, oils, perfumes, 



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