HABITS OF PLANTS. 
203 
to be considered; although the soil and the quantity of moisture 
should be rendered as similar as possible to those of its native 
habitation. Plaix..s from warm climates are gradually accus- 
tomed to a lower temperature by placing them in hot-houses, 
then in green-houses, and lastly, in the open air. Plants vary 
in their susceptibility of naturalization. The horse-chestnut^ 
which is now common in the Middle and Northern United 
States, was originally brought from the tropical regions. In 
these regions, however, it usually grows in grounds somewhat 
above the level of the sea, and therefore its habit, as to tem- 
perature, renders it in some degree fitted for more northern 
countries. Orange and lemon trees cannot be brought to bear 
the roughness of our climate without some protection. In many 
{i2i^Q^^ perennial plants hy this change of climate are converted 
into annual ones ; as if fearing the inclemencies of a cold win- 
ter, they pass through their successive stages of existence with 
rapidity, and accomplish in one summer what they had been ac- 
customed to require years to perform. The nasturtion was ori- 
ginally a perennial shrub, flourishing without cultivation on the 
banks of the Peruvian streams ; yet, transferred to this country, 
it is an annual herbaceous plant, which completes its term of 
existence in a few months. 
311. The acclimating of some plants is with difiiculty accom- 
plished ; others change their habits more readily, as Indian 
corn^ which, aided by climate and culture, suffers a remarkable 
change. After having been for several years raised in Canada, 
it arrives to perfection in a few weeks, and on that account is 
employed in New England for earhj corn ; but that which has 
been for years cultivated in Virginia will not ripen in a New 
England summer ; yet originally, the early corn of Canada and 
that of Virginia were the same, both in habit and other proper- 
ties. While merely ornamental or curious plants can with diffi- 
culty be made to vegetate freely in foreign situations, the vege- 
tables most useful to man are disseminated and cultivated. The 
delicate exotic flowers often disappoint our expectations ; but 
the wheat, the potato, and corn, which are also exotics, seldom 
withhold their fruits from the labor of the husbandman. Thus 
should earthly parents, imitating their " Father in heaven," 
first provide their children with what is useful both for body 
and mind, leaving the ornamental to be bestowed or not, as 
circumstances may render proper. 
312. Agents which affect the Growth of Plants. — Of the vari- 
ous substances by which vegetables are nourished, water seems 
the most important. Some plants grow and mature with their 
A'oots immersed in water, without any soil ; most of the marine 
Plants, as to naturalization.— 311. Indian-corn— Useful vegetables easily cultivated.— 312. AgenUi 
Utat afffect tlie grovv tli of plants— Water. 
