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2. The damage done by insects in Iowa averages 

 58 cents per acre. What would this amount to for 

 your county? For the farm you live on? 



3. Wild birds average about 450 to the quarter 

 section. How many would this be for the county? 

 For your farm ? 



4. Allowing that each bird eats 50 insects per day 

 (a low estimate), how many insects would the birds 

 of the county destroy in the five summer months? 

 How many on your farm ? 



5. Estimating 100,000 insects to the bushel, how 

 many bushels would this be ? How many bushels per 

 day? 



6. The birds that stay all winter eat principally 

 weed seed. Allowing one bird to the acre and % 

 ounce of weed seed per day for each bird, how many 

 tons of weed seed would the birds eat in three months 

 in the whole county? How many pounds on your 

 farm? 



7. One plant of plantain bears about 14,000 seeds, 

 weighing about one ounce. Forty of these seeds will 

 easily seed a square yard of ground. Suppose all the 

 seeds were allowed to live, how many square yards 

 of ground would one plant seed? What harm do 

 plantain and such weeds do ? How can we keep them 

 from spreading and crowding out the crops? 



8. Five hundred small grasshoppers will eat a 

 pound of growing crops in a day. Almost all birds 

 are fond of grasshoppers for food. A cuckoo or a 



