16 HORTICULTURAL MANUAL. 



seeds were planted. If practicable, the budding and 

 grafting of seedlings standing where the seed is planted 

 would prove a great advantage. But in this case the roots 

 that favor rapid and thrifty growth of the top are not as 

 favorable for transplanting as those that have been trans- 

 planted. 



18. The Office of the Roots. The roots of trees and 

 plants serve the purpose of holding the top erect and to 

 supply water, with its dissolved elements, for sustaining 

 growth of the tree or plant. The deep roots take up the 

 water mainly and the surface-roots largely take up nitrates 

 and other essentials of growth. The soil conditions have 

 much to do with the vigorous growth of roots and the 

 closely related tops. In Nature the extension of roots in 

 the soil favor the admission of the oxygen of the air, and 

 the leaves that accumulate give the needed supply of leaf- 

 mould and nitrogen required for healthy growth. On the 

 other hand," the clean culture of the orchard and small 

 fruit-plantation without the application of barn-yard 

 manure or other organic material, will soon so change the 

 mechanical condition of the soil that air cannot enter to 

 give life and growth to the protoplasm of newly formed 

 and growing roots. The continued clean culture without 

 the application of vegetable matter will soon take the 

 humus from the soil and starve the roots and whole plant- 

 growth by lessening the supply of nitric acid and its com- 

 bination with alkalies, such as nitrate of soda and other 

 useful plant-nutrients. 



19. Root-protection. It may be said that Nature pro- 

 tects tree- and plant-roots by shading in summer and 

 surface-protection in winter. Under clean culture the 

 bare surface is heated abnormally between the rows of 

 cultivated trees to such extent that surface-roots and root- 

 hairs cannot come near enough to the surface to reach the 



