154 ACTION OF THE SOIL ON PLANTS. 



I 



can change its nature. Hence the impracticability of 

 cultivating the sandy deserts of Arabia, Africa, and vari- 

 ous other parts of the world. 



Emily. Yet, if such deserts existed in Europe, do you 

 not think that means would be discovered to overcome 

 the difficulty ? 



Mrs. B. I doubt it. The wind which blows without 

 restraint over these unsheltered and unstable plains tears 

 up the roots of every tree that is planted. 



Emily. But small low shrubs would offer but little re- 

 sistance to the wind. 



Mrs. B. These would soon be buried by the whirl- 

 winds of sand. The plants most likely to succeed would 

 be such as are of moderate stature, with spreading roots 

 to fix them in the soil. 



When sands are of small extent they may be improved 

 by mixing clay with them ; and the first crop should be 

 raised solely with the view of ameliorating the soil. 



There are three species of sandy soil : that which forms 

 the banks of rivers; that which composes those extensive 

 plains called steppes ; and that which forms sand-hills 

 on the sea-shore. On the borders of rivers, stakes of 

 willow and of alder may be planted with advantage ; be- 

 ing abundantly watered, they soon shoot out roots and 

 branches, which grow rapidly. Then, if with the stroke 

 of a hatchet these branches be lopped, so as to make 

 them trail upon the ground, without being completely 

 separated from the stem, they will soon be covered with 

 the loose soil and will strike fresh roots : these numerous 

 roots shooting out in every direction, are interwoven, and 

 forms a species of net work, which sustains and gives 

 stability to the soil. 



In order to bring steppes into culture, which are not 

 so well supplied with water, the first plants raised must 

 have roots which pierce deep into the earth, so that they 

 may find water beneath the sandy soil. The culture of 

 madder has been successfully employed in the neighbor- 

 hood of Haguenot, as the precursor of general agriculture. 



848. Why would they not be cultivated if in Europe 1 849. What 

 would become of low shrubs'? 850. When sands are of small extent, 

 how can they be improved! 851. What are the three species of sandy 

 soil named! 852. How is it said that the soil can be improved on 

 the borders of rivers, by planting willows and alders'? 853. How are 

 ateppes brought into culture! 



