210 FLOWERING AND ITS CONSEQUENCES. 



in a few weeks or months after they spring from the seed, when 

 they have little nourishment stored up in their tissue ; and their 

 lives are destroyed in the process (127) : biennials flower after a 

 longer period, rapidly exhausting the nourishment accumulated in 

 the root during the previous season, and then perishing (128); 

 while shrubs and trees do not commence flowering until they are 

 sufficiently established to endure it. The exhaustion consequent 

 upon flowering, however, is often exhibited in fruit-trees, which, 

 after producing an excessive crop (especially of late fruits, such as 

 apples), sometimes fail to bear the succeeding year. When the 

 crop of one year is destroyed, the nourishment which it would have 

 consumed accumulates, and the tree may bear more abundantly 

 the following season, and so on alternately from year to year. 



368. The actual consumption of nourishment in flowe'ring may 

 be shown in a variety of ways ; as by the rapid disappearance of 

 the farinaceous or saccharine store in the roots of the Carrot, Beet, 

 &c., when they begin to flower, leaving them light, dry, and empty ; 

 and from the rapid diminution of the sugar in the stalk of the Sugar- 

 cane (as also in that of Maize) at the same period. The stalks 

 are therefore cut for making sugar just before the flowers expand, 

 as they then contain the greatest amount of saccharine matter. 



369. The consequences of this exhaustion upon the duration of 

 plants have already been adverted to. They are further illustrated 

 by the facility with which annuals may be changed into biennials, 

 or their life prolonged indefinitely, by preventing their flowering ; 

 while they perish whenever they bear flowers and seed, whether 

 during the first or any succeeding year. So, a common annual 

 Larkspur has given rise to a double-flowered variety in the gardens, 

 which bears no seed, and has therefore become a perennial. So, 

 also, cabbage-stumps, which are planted for seed, may be made to 

 bear heads the second year by destroying the flower-shoots as they 

 arise ; and the process may be continued from year to year, thus 

 converting a biennial into a kind of perennial plant. The effect of 

 flowering upon the longevity of the individual is strikingly shown 



do not bear flowers, but push forth into leafy branches. So the flowers of 

 most trees and shrubs that bear large or fleshy fruit are produced from lateral 

 buds, resting directly upon the wood of the previous year, in which a quantity 

 of nutritive matter is deposited. So, also, a seedling shoot, which would not 

 flower for several years if left to itself, blossoms the next season when in- 

 serted as a graft into an older trunk, from whose accumulated stock it draws. 



