CHAPTER XLII 

 PLANTS, HELPFUL AND HARMFUL 



On every railway we see long freight trains made up of 

 cars from every section of the country. In our great har- 

 bors we find steamers from every quarter of the world. 

 Much of the freight of these carriers consists of plant 

 products being brought to our doors from the points of 

 growth or manufacture. 



Once man depended for food, shelter and clothing on 

 what grew about him. Today, if we trace to their source 

 the foods, spices, medicines, clothing, and furnishings we 

 use, we find the plant life of the entire world contributing 

 to our health, comfort and pleasure. 



The plants that are most beneficial to mankind include those 

 that produce materials for bread, building, beverages, ropes and 

 twine, condiments, dyes, fabrics, medicines, oil, and sugar. Plants 

 used for ornamental purposes might also be mentioned. 



Food Plants. The important food-producing plants are 

 wheat, Indian corn, rice, millet, barley, rye, buckwheat, oats, 

 cassava, arrowroot, the cocoanut, sago and date palms, sugar cane, 

 the potato, the beet, and the sugar maple. Wheat, Indian corn, 

 rye, oats, barley, and rice are commonly known as cereals, and are 

 materials used for making bread and "breakfast foods." Of 

 these plants wheat is considered the most valuable, since it con- 

 tains, in the best proportion, the different food substances, espe- 

 cially the protein and starch, needed for the nutrition of the body. 

 Of hardly less importance is rice, which contains a larger per- 

 centage of starch than the other cereals, and constitutes the chief 

 food of more than one-third of the inhabitants of the world. In 

 India, China, Japan, and the islands off the coast of Asia it is 

 used most extensively. 



Next to the cereals in starch-producing value stands the 

 potato. Since its discovery over three hundred years ago it 

 has steadily advanced in favor as an article of food, and is 



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