CHAPTER NXT 
ORIGIN OF FARM AND GARDEN VEGETABLES AND 
MISCELLANEOUS PLANTS 
The potato. The sweet potato- Miscellaneous tubers. Edible roots. The 
onion - The beet - Manioc, or mandioca- The turnip - Miscellaneous roots - 
Vegetables cultivated for their foliage . Cabbage - Celery - Lettuce - Aspara- 
gus - Plants cultivated for beverage - Coffee - Tea - Maté- Plants grown 
for sedative effect - The poppy - Coca- The betel - Tobacco - Fiber plants - 
Cotton . Flax- Hemp - Ornamental plants - Weeds 
Many plants have a habit of sending out not only the upright 
stems that bear leaves, but also others that run along just above 
or just beneath the surface of the ground, and, by branching or 
sending out roots at the joints here and there, are able to prop- 
agate themselves without the help of seeds. Strawberries do 
this with “runners” above the ground. Quack grass and Canada 
thistle do the-same, except that the stems run just below the sur- 
face, a habit which makes these two weeds peculiarly difficult to 
eradicate. Blue grass has the same habit, but, being valuable in- 
stead of worthless, we count the custom a virtue and not a vice. 
In a few plants these underground stems greatly thicken, and 
these thickened stems, called tubers, are favorite foods, generally 
as a source of starch. 
The potato (Solanum tuberosum). The most common and the 
most valuable of all plants of this order is the ordinary Irish 
potato. Its name ‘‘Irish”’ is a misnomer,’ as it is truly an Ameri- 
can product, its wild progenitor still being common along the 
coast of Chile and in the higher elevations to the northward. 
Several closely related species abound in the highlands of South 
and Central America as far north as Mexico, and a not distantly 
1 Bestowed from the fact that the cessation of the periodic famine in Ireland 
dates from the introduction of the. potato. 
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