14 THE PLANT. 



plant, with a stem half as high again and a much greater 

 number of twigs and leaves. The organic labour of this 

 new plant, during the second year, results in the genera- 

 tion agam of products which are deposited in the root, 

 and, proportionately to the greater extent of the organs of 

 nutrition, are stored up in much greater quantity than 

 the roots had originally supphed. 



The same process is repeated in the third and fourth 

 years ; in the fifth and sixth years the store deposited in 

 the roots has become sufficiently rich to produce in spring, 

 when the weather is warm, three, four, and more stems as 

 thick as a finger, with numerous branches covered with 

 leaves. 



A comparative examination of the green asparagus 

 plant, and of its withering stems in autumn, seems to 

 indicate that at the end of the period of vegetation the 

 remainder of the dissolved or soluble substances fit for 

 future use, then still remaining in the overground organs, 

 descend to the root. The green parts of the plant are 

 comparatively rich in nitrogen, alkalis, and phosphates, 

 whilst in the withered stems these substances are found 

 in small quantities only. The seeds alone retain compa- 

 ratively large proportions of phosphated earth and alkahs, 

 being nothing else than the excess of those substances 

 which the roots do not require for the next year. 



The imderground organs of perennial plants are the 

 economic gatherers of all the vital conditions necessary 

 for certain functions. If the soil will allow, they always 

 collect more than they give out ; they never spend all 

 they receive. These plants form their flowers and seeds 

 when the roots have collected a certain excess of phos- 

 phates, which may be given up without endangering the 

 existence of the plant. An abundant supply of nourish- 

 ment, by means of manuring, will accelerate the develope- 



