CHAPTl-R IX. 



PROPAGATION OF PLANTS. 



The basic principle of all horticultural opera- 

 tions is a thorough knowledge of tJie plant and 

 its eni'ironmeiit. This necessitates a careful 

 study of the nature and conditions of the seed- 

 line throuohout its develoijnient from the em- 

 bryo to the adult plant. 



^.—PROPAGATION FROM SEEDS. 



SEEDS AND SI KDLINGS. 



L The Seed-coat. 



Examine the outer covering of a number of dif- 

 erent seeds — as, the corn, bean, squash, peach, 

 '-'jnna, and locust^noting carefully the difference 

 in their textures. If these seeds be planted at 

 the same time and under the same conditions, 

 they will show equally as great variations in the 

 time which they require for germination. 



In nature, the hard, tough seeds of many or- 

 chard and forest trees — as, apple, peach, and 

 hickorv — are buried beneath the litter of the 

 orchard or forest, where they are subjected to 

 winter snows and changes of temperature until 

 their outer coverino-s are softened or cracked, so 

 that the embryonic plant may develop, while 

 the seeds of such species as the catalpa (Fig. 

 50), honey-locust, and Kentucky coffee-bean re- 



201 



