THE STEM 83 
92. Biennials, as the name implies, live for two years. 
Their energy during the first season is spent chiefly in laying 
by a store of nourishment, 
usually in the tissues of 
fleshy roots (70). By this 
means they get a good start 
in the second season and 
mature their seeds early. 
Many of our common gar- 
den vegetables, such as tur- 
nips, carrots, parsnips, and 
cabbage, belong to this 
class. Where is the nour- 
ishment stored in the cab- ‘ a 
bage? Fic. 93.— A biennial plant, mullein, in 
93. Perennials are plant 3 winter condition with stem reduced to 
7 : little more than a disk supporting a rosette 
that live on indefinitely, like ofleaves. Notice how close they cling to 
the earth, and compare them with their 
most of our forest trees fruiting condition a few months later as 
and woody-stemmed shrubs. *2°w2 in Fig. 237. 
Woody stems are usually perennial and may live for hun- 
dreds and even thousands of years, as those of the giant 
sequoias of California, and the famous chestnut of Mt. 
Etna. 
94. Herbaceous stems are more or less succulent and die 
down after fruiting. They are usually annuals, though some 
kinds, like the garden geraniums and the common St.-John’s- 
wort, show a tendency to become woody, especially at the 
base, and live on from year to year. Others, such as the 
hawkweed and dahlia, die down above ground in winter, 
but are enabled to keep their underground parts alive indefi- 
nitely, through the nourishment stored in them, and are 
thus perennial below ground and annual above. Woody- 
stemmed annuals, such as the cotton and castor oil plant, 
are not, properly speaking, herbs. In the tropical countries 
to which they belong they are perennial shrubs, or even 
small trees, but on being transplanted to colder regions 
