CHAPTER XXX 
SOME USEFUL PLANTS 
403. Definition of Economic Botany; Subdivisions. — 
Economic botany treats of the uses of plants to man. Be- 
ginners in botany can only afford time for a brief summary 
of the principal uses of a few of the most important plants. 
Some of the principal classes of plant products valuable 
to the human race are these: 
(1) Foods for man. 
(2) Medicinal plants and their products. 
(3) Foods for domestic animals. 
(4) Fertilizers of vegetable origin. 
(5) Tanning materials, dyes, varnishes, and miscella- 
neous products of vegetable origin. 
(6) Plant fibers, hairs, and similar products. 
(T) Plants cultivated for ornament. 
(8)1 Timber and cabinet woods. 
(9)1 Fuel. 
(1) FOODS FOR MAN 
404. The grains constitute the main part of our food 
supply, from vegetable sources, and are especially valuable 
on account of their concentrated character and their keep- 
ing qualities. The principal grains are wheat, oats, rye, 
barley, rice, and Indian corn. They are all the fruits of 
1 These two classes are for convenience treated in Chapter XXXI. 
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