NITROGEN-CONSUMING PLANTS 225 



bounds, an enumeration of these nitrogen-consuming plants will be made 

 here. 



ROOT CROPS 



The root crops are those which represent the underground root, or 

 stem of the plant which is cultivated. Enumerated the plants are: 



Potato (Solanwn tuber osum), a native of America and cultivated for 

 its enlarged, starch-filled tubers. 



Sweet Potato (I pomoea ^batatas) originally from the West Indies and 

 Central America. It is cultivated for its fleshy roots filled with starch. 



Radish (Raphanus sativus] is a native of the temperate regions of the 

 old world and is raised for its fleshy tap root. 



Horse-radish (Radicula armor acia) . This plant is a native of Europe 

 and has a white, fleshy, cylindrical root, which is grated and used as a 

 condiment. 



Turnip (Brassica napus). The turnip is a biennial plant producing 

 an edible, fleshy tap root. It is a native probably of Europe, or Western 

 Asia. 



Rutabaga, or Swede Turnip (Brassica campestris). The fleshy edible 

 root has a short stem, or neck, at its upper part which distinguishes it 

 from the turnip. It is used as food for stock and occasionally as food for 

 man. 



Beet (Beta vulgaris). This is a complex species separated into 

 several well-marked groups, as the sugar beet, mangel-wurzels and com- 

 mon garden beet. The wild beet occurs along the coasts of southern 

 Europe as a perennial sea beet (Beta maritima) with a tough, slender root. 



Jerusalem Artichoke (Helianthus tuberoses). The thick, fleshy root- 

 stocks with oblong tubers are the parts used as food. This native 

 American plant is also called earth apple, Canada potato, girasole and 

 topinambour. 



Carrot (Daui^us carota). The conical root of the carrot is an important 

 food. The carrot is a biennial plant native of Europe and Asia. 



Parsnip (Pastinaca saliva}. The fleshy root of the cultivated plant 

 has been developed from a thin, tough, woody root and hypocotyl. It is 

 a native of Europe. 



Celeriac (Apium graveolens). This vegetable is the turnip-like root 

 of the celery plant, originally a wild plant of Europe. 



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