cently, a decade ago, and a generation ago. Compare the dominant forms of plant 

 life in each with that found in virgin timberland. Work out the succession of plants 

 which develop in your region when forests are cut or destroyed. 



QUESTIONS 



1 Why does a plant or animal sometimes thrive better when carried to a 

 strange region."^ 



2 How can insects that are not harmful in one region do great damage in 

 another region? 



3 How can insects that are harmless at one time become injurious at another 

 time.? 



4 What conditions allow one pest or one disease to increase with extreme ra- 

 pidity at times? 



5 What are some of the dangers of interfering with the natural balance of life? 

 What are some of the consequences of man's interference with it? 



6 What are the chances that man's fight against insects will someday be 

 finished? Why? 



7 What can be done to make possible a larger population without undue 

 crowding? 



8 What animals or plants would it be desirable to exterminate from your 

 region? Why? 



9 How could the extermination of any plant or animal species bring about 

 undesirable consequences? 



10 What is the most effective way to fight any epidemic? 



11 What dangers threaten our forest areas? 



12 What do you consider the most valuable organic resource of the country? 

 To what extent are we husbanding this resource? 



599 



