THE PLANT GENERATION 



9. A generation begins with the ijoung seed, not with 

 germination. It ends with death — that is, when no life is 

 left in any part of the plant, and only the seed or spore 

 remains to perpetuate the kind. In a bulbous plant, as a 

 lily or an onion, the generation 

 does not end until the bulb dies, 

 even though the top is dead. 



10. When the generation is 

 of only one season's duration, 

 the plant is said to be annual. 

 When it is of two seasons, it is 

 biennial. Biennials usually bloom 

 the second year. When of three 

 or more seasons, the plant is 

 perennial. Examples of annuals 

 are pigweed, bean, pea, garden 

 sunflower; of biennials, evening 

 primrose, mullein, teasel, par- 

 snip, carrot ; of perennials, 

 dock, meadow grass, cat-tail, 

 and all shrubs and trees. 



11. DURATION OF THE 

 PLANT BODY. — Plant struc- 

 tures which are more or less 

 soft and which die at the 



close of the season are said to be herbaceous, in contra- 

 distinction to being ligneous or woody. A plant which is 

 herbaceous to the ground is called an herb; but an herb 

 may have a woody or perennial root, in which case it is 

 called an herbaceous perennial. Annual plants are classed 

 as herbs. Examples of herbaceous perennials are butter- 

 cup (Fig. 2), bleeding heart, violet, water-lily, many 

 grasses, dock, dandelion, golden rod, asparagus, rhubarb, 

 many wild sunflowers (Figs. 3, 4). 



12. Many herbaceous perennials have short generations. 



