CH. IX.] DEATH AND DECOMPOSITION. 31 1 



doubt that it is the exhaustion consequent upon 

 the production of seed. Scarcely an annual exists 

 which usually dies at the close of the season, after 

 ripening its seed, but may be made to retain a vigorous 

 existence if its inflorescence be removed as speedily 

 as formed. Mignionette is a very familiar example, 

 for this may be allowed to bloom, but if its flower 

 stalks be cut down before the seed-vessels are per- 

 fected, it becomes woody and shrubby, and ^^ill live 

 and bloom for three or more successive years. If 

 allowed to ripen its seed, it dies the same autumn. 

 The common nasturtium is an annual, but the 

 double nasturtium, says M. De Candolle, has be- 

 come a perennial, because its flowers, deprived of 

 the faculty of producing seeds, do not exhaust the 

 plant, and it is probable that every annual, rendered 

 double by cultivation, will become a perennial. 



This explains why fniit trees are weakened, or 

 rendered temporarily improductive, and even killed, 

 by being allowed to ripen too large a crop of fniit, 

 or to " overbear themselves," as it is emphatically 

 tenned by the gardener. 



The thinning of fruit is, consequently, one of the | 

 most important operations of the garden, though \ 

 one of the least generally practised. On the weaker 

 branches of the nectarine and peach, an average 

 space of nine inches should be between each 

 brace of fruit, and on the most \'igorous wood 



