52 OF THE ROOT. 



Perennial roots are those whose existence is prolonged a 

 number of years to an indefinite period ; as the asparagus, ge- 

 ranium, and rose ; also trees and shrubs. Climate and cultiva- 

 tion affect the duration of the roots of vegetables. Many pe- 

 rennial plants become annual by transplanting them into cold 

 climates: the garden nasturtion, originally a perennial shrub 

 in South America,has become in our latitude an annual plant. 



Botanists express the duration of vegetables by the use of 

 astronomical signs ; the annual plants are designated thus $&, de- 

 noting one revolution of the earth around the sun. 



The biennials are represented by $, the planet mars, which 

 makes its revolution in two years. 



The perennials are represented by If, the planet Jupiter, 

 which makes its revolution in many years. 



The character *? , the sign of the planet Saturn, is used to 

 designate woody plants which usually live many years. 



It is said, that great care in the culture may prolong the 

 life of annual plants beyond what appears to be their natural 

 term of existence. 



Forms of Roots. 



There are seven varieties in the forms of roots ; branching, 

 fibrous, spindle, creeping, granulated, bulbous. 

 Fig. 12. 



1st. Branching Root, 

 (Radix ramosa.) (Fig. 12.) 

 This is the most common 

 kind ; it consists of numer- 

 ous ramifications, resem- 

 bling in appearance the 

 branches of a tree ; some of 

 these branches penetrate to 

 a great depth in the earth, 

 and others creep almost hor- 

 izontally near its surface. 

 Experiments have been made, which show, that branches by 

 being buried in the soil may become roots ; and roots, by being 

 elevated in the atmosphere, become branches covered with 

 foliage. We often see the roots of trees, which have been 

 blown down, throwing out leaves. 



Branching roots terminate in fibres or radicles, which are in 

 reality the proper roots ; as they imbibe through pores, the 

 nourishment which the plant derives from the earth. Nature 



Perennial roots Classification of roots as founded upon their forms Branch- 

 ing root. 



