FARM CROPS 97 



10. Give examples of summer catch crops. 



11. Give examples of plants used as winter cover crops. 



12. Give several uses of catch crops and cover crops. 



13. Should such crops be used in young orchards or in old ones? 



14. How do they benefit the soil and trees? 



15. Give an example of a three-year rotation of crops. 



16. Tell when each of these crops is planted and harvested. 



17. Give an example of a rotation system where potatoes are the 

 special crop desired. 



18. Repeat the four-year rotation given in the book for dairy farms. 



19. Describe a good rotation where alfalfa is grown. 



20. What is succession cropping? Give examples. 



21. What is companion cropping? Give examples. 



References. U. S. Farmers' Bulletins : 318, Cowpeas ; 509, 

 Forage Crops for Cotton Region; 515 and 529, Vetches; 550 and 646, 

 Crimson Clover. 



CHAPTER X. 

 FARM CROPS. 



Classification of Crops. Field crops are those which are 

 most commonly grown in fields; they are sometimes also 

 grown in gardens. Those usually found in gardens only 

 are called horticultural crops; these include all fruits and 

 flowers and most vegetables. 



Crops of all kinds may also be classified according to the 

 following six groups: 



1. Forage and Fiber Crops. These include grasses, clo- 

 vers, and alfalfa, used for green forage, for hay, or for pas- 

 ture; and cotton, flax, and hemp, used for fiber. 



2. Cereal Crops. The grains are called cereals. These 

 include corn, wheat, oats, barley, rye and emmer. 



3. Tuber Crops. White or Irish potatoes are true tubers; 

 sweet potatoes are usually also classified with tubers, but 

 strictly speaking they are believed to be roots. 



4. Root Crops include many that are used for stock feed, 

 such as mangels, field beets, beets, turnips, carrots. 



5. Market-garden Crops. Here we find cabbage, cauli- 

 flower, celery, onions, lettuce, radish, table beets, melons, 

 and many others. 



