CHAPTER IV 



PLANT PROPAGATION 



The soil receives in its bosom the seed scattered broadcast upon it, soft- 

 ened and broken up ; she first keeps it concealed therein ; next, when it has 

 been warmed by the heat and by close pressure, she splits it open and draws 

 from it the greenery of the blade. CICERO 



37. How plants are propagated. Comparatively few of our 

 principal food plants live longer than a single year. Almost a 

 new generation of plants must be produced at the opening of 

 each new season. To understand how plants multiply, there- 

 fore, is fundamental to the successful production of crops. 



All cultivated plants come from seeds, spores, or from some 

 form of bud growth. Nearly all farm and garden crops are 

 grown from seeds, but only a few of the fruit trees are prop- 

 agated in this way. The important field crops not grown 

 from seeds are sugar cane, Irish potatoes, and sweet potatoes. 

 Apples, peaches, pears, oranges, and other fruits, with few ex- 

 ceptions, will not come true from the seed, and are therefore 

 propagated by means of bud growth. 



38. How a plant comes from the seed. In every live seed 

 there is a living plant in an undeveloped state. This is the 

 part of the seed called the germ, or embryo (Fig. 18). The 

 embryo is usually but a small part of the seed. The bulky part 

 of most seeds consists of food (principally starch and oil), which 

 has been stored by the parent plant. This food feeds the germ, or 

 embryo, while it is sprouting ; it also feeds the young plant until 



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