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OTHER FLOWERING PLANTS 
people dislike to think of them as obnoxious plants. But they 
prevent the grass from growing, and cattle will not eat 
them either in the winter or in the summer, so that they are 
a nuisance to the farmer. A weed, then, may be defined as a 
plant which interferes with the growth of some useful plant. 
Weeds are successful in growing and in living, because they 
have strong roots, produce many seeds, and have numerous 
devices for distributing their seeds. 
HOME WORK 
Consulting any maps which show where most of our common food 
plants are raised, make a note of the states which produce the greatest 
quantity of each. What is the leading industry in these states ? What 
industries are related ? Why ? Find pictures showing how some of these 
crops are harvested. What industries are concerned with manufactur¬ 
ing the products of these states ? What one in distributing the man¬ 
ufactured products ? By what routes are most of them shipped ? Why ? 
What are the leading crops in your township? in your county? in 
your state ? What foods do you have to bring from other states ? Why ? 
Try to think how climate, kind of soil, and the needs of the community 
influence the farmer as to the kinds of crops he plants. Notice what he 
does with the surplus. Find out from government reports how much 
grain was sent to Europe during the war. Find out how the number of 
bushels of grain produced' per acre compares with that in other coun¬ 
tries. Account for the facts you learn. How can a knowledge of biology 
help a farmer ? 
SUMMARY 
The flowering plants are the most highly developed of 
all the plants and bear an intimate relation to mankind. 
The many grasses and cereals furnish animals and man 
with much of their food. The cultivation of these plants 
has aided the development of civilization. 
QUESTIONS 
What plants furnished part of your food to-day ? In what part of the 
plant was this food made ? In what part stored ? What fruits do you 
eat? Which plants grow these fruits? Where do these plants live? 
Name plants, parts of which are used in medicine. What plants are used 
