18 :©otani2 



The office of the root is : I. To obtain nutriment 

 for the plant. 11. To hold or moor the plant to the 

 gromicl. III. To store up food for future use. 



Most roots are fixed in the earth. There are also 

 air or aerial roots, such as the ivy and trumpet- 

 creeper send forth from the sides of the stem to 

 serve as hands, to grapple the supports upon which 

 they climb. Other aerial roots penetrate the bark of 

 branches wpon which they have fixed themselves, 

 and then suck out sap for food. 



Roots are called annual, when they live but one 

 year ; biennial, when they live for two years ; per- 

 ennial, or ever-enduring, when they live for many 

 years. Some plants live over a thousand years. 

 Ivies are noted of five hundred years old ; a grape- 

 vine eight hundred years old ; trees a thousand 

 years old. 



Roots naturally perennial may become annual 

 when transplanted to colder than their native places. 

 Cold, however, does not kill all roots, it merely sus- 

 pends much of their activity. 



When we walk about in January and see the 

 earth frozen, or covered with snow, we need not 

 fancy that all is still and dead under ground. There 

 are millions of mouths below the surface, taking their 

 rest, and feeding but little ; there are other millions 

 of plant store-houses, food-full, for coming summer ; 



