CHAPTER XXVI. 



THE VEGETATION OF SALINE AND ALKALI LANDS. 



Marine Saline Lands. While the saline alluvial lands of 

 the sea-coast differ both in their mode of origin and in their 

 nature from the alkali soils or " terrestrial saline lands," as 

 they have been called in Europe, their vegetation has in many 

 respects a common character. Not only is there much simi- 

 larity, sometimes even identity, in the kinds of plants inhab- 

 iting these lands, but their saline ingredients induce certain 

 changes of form and structure in plants not properly " saline " 

 but more or less tolerant of soluble salts, by which the saline 

 or alkali character of the lands may be recognized. 



Just as in the case of lime \ve must distinguish between the 

 plants definitely repelled by a large amount of this substance 

 in the soil (calcifuge), while others prefer the soils in which 

 lime is abundant (calciphile) , and still others appear to be in- 

 different to its presence and are governed in their habitat 

 by the physical conditions presented : so in the case of saline 

 lands the salts may attract or repel certain plants. The lat- 

 ter class is much the largest ; while there is also a number of 

 plants which are more or less indifferent to the presence of 

 salts, provided these be not in very great excess. Such plants 

 constitute the next-largest class; while those attracted by salts, 

 and whose welfare is conditioned upon their presence, are 

 comparatively few in number, and still fewer among them are 

 of economic importance. Hence the soluble salts have largely 

 a negative importance for agriculture; the question usually 

 being how to utilize the land until the undesirable surplus of 

 salts can be got rid of, partially or wholly, as the case may be; 

 the former usually in sea-shore lands, the latter in the alkali 

 lands proper; in which a small remnant, not sufficient to injure 

 crop plants, is usually desirable (see chapt. 23. p. 462). 



General Character of Saline ]\"gctation. Those familiar 

 with seashore marshes cannot fail to note the tleshincss and 



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