22 BULLETIN 1409, U. S. DEPARTMENT OF AGRICULTURE 
In sections of little rainfall the tamarisk is much used for hedges 
and windbreaks. 4 
PLANTS 
Aside from trees, shrubs, air plants, vines, and cactus, plant 
life is poor in the mountainous, semiarid, and wooded regions. 
Throughout the Pampa and Mediterranean regions grass, forage 
plants, cereal crops, and weeds are most general and important. The 
native coarse bunch grasses (pasto duro) are most common, with 
some finer grasses (pasto tierno) mixed in between. Various species 
of clover, medicago, and legumes grow spontaneously. Alfalfa 
thrives without liming or inoculation. Cebadilla, bluegrass, rye 
grass, various stipas, vetches, sweet clovers, alfilerillo, and many other 
grasses and weeds eaten by livestock are common. 
The most conspicuous plants in summer are the various species of 
giant thistles, cardo de Castilla (Cynara cardunculus Tr.), cardo 
negro (Cirsium lanceolatum C), and cardo Asnal (donkey thistle). 
These thistles grow higher than a man's head, as thick as they can 
stand, and cover hundreds of square miles. When in bloom they 
form a sea of pink and reddish purple as far as the eye can see. 
When the seeds ripen the silken parachutes fill the air like trans- 
parent snowflakes. Although cattle and horses break paths through 
these forests of thistles and browse on the leaves, they are regarded as 
a troublesome pest and on some of the ranches efforts are made to 
cut them with mowing machines just before blossoming. The 
infested areas are so great that it will be impossible to control these 
thistles until the estates are subdivided into smaller units, more of 
the land is brought under cultivation, and population increases. 
Foxtail (cola de zorro) covers large areas and the Kussian thistle, 
cocklebur, and Bermuda grass are pests. Wild mustard, turnip, and 
a small yellow-flowered chicory are especially bad in the grain and 
alfalfa fields. 
Among the characteristic bunch grasses of Argentina, the highly 
ornamental Pampas grass (Gynerium argenteum) is widely distributed. 
It prefers moist ground and grows from 3 to 10 feet high, usually in 
isolated bunches or colonies. It seems to flourish best in the Chaco. 
Its stately silver plumes can be seen waving in the glades of the wooded 
country and across the open prairies. Many of the plumes are 3 feet 
long, 8 inches in diameter, borne on bamboolike stems. 
The marshes and margins of lagoons and streams are grown up 
with rushes, reeds, and cattails, and stagnant water, especially in the 
north, is usually covered with water lilies, hyacinths, and other 
aquatic plants. Wild carinas grow in damp places, and wild verbena 
with scarlet, purple, or - white flowers, bright-red Portulaca, a pink- 
flowered oxalis, evening primose, and goldenrod are widely dis- 
tributed. Castor beans are grown in fields and about the houses in 
the north country and often grow wild along ditches and roadsides. 
Some of these plants attain the size of a small tree with woody stems 
6 inches or more in diameter. An ornamental plant frequently seen 
about houses and on walls and fences is a native clematis which 
4 For a more complete list of the trees and shrubs of Argentina see pp. 198 216 of C. D. Girola's Investi- 
gation agricola en la Republica Argentina. Buenos Aires, Compahia Sud-Americana de billetes de banco, 
1904. (Republica Argentina. Anales del Ministerio de agricultura. Section agricultural botanica y 
agronomia. Agronomia. t, I, n. 1). 
