Seasides and Strand Plants 



Most of these plants have smooth, more or less suc- 

 culent leaves, for like Salicornia they have to endure 

 from .04 to nearly 5 per cent, of salt water.* Now 

 several experimenters have directly produced fleshy 

 leaves, quite of this character, by supplying, for instance, 

 garden wallflowers with salt instead of fresh water.^ 



So that this fleshiness seems to be a fitting reaction 

 caused by the salt, and also helping the plant to resist its 

 poisonous effect by living in a thirsty sort of way. 



Such Armeria flats vary considerably. On the Clyde 

 one may find exquisite dark green mats of the Alga 

 Vaucheria filling up the interstices between the other 

 plants, and firmly attached to the dark mud by hundreds 

 of rhizoids. The elastic strength of such a Vaucheria 

 cushion is very remarkable, as one can see by cutting 

 out a square foot and holding it up by one corner. Such 

 fat, dark soil as one finds along the Clyde is probably 

 full of organic matter, but it is kept well aerated by 

 various small worms. There may be as many as 

 fifteen of their burrows in a square inch of surface. 



Cattle and sheep browse at low tide upon the 

 Armeria flats, where indeed they grow fat and flourish 

 exceedingly. 



But on the landward sidcy where the salt is being 

 gradually drained out, and where the level of the soil 

 has so much increased in height that even the highest 

 tides but rarely extend to it, a new process is beginning. 



Rushes (J. lamprocarpus), sedges, and a few grasses 

 (Agrostis, Festuca alba var. stolonifera) are beginning to 

 encroach upon the Armeria country, and if they once suc- 

 ceed in getting a root-hold, other weeds come in (couch- 

 grass, cock's-foot, Yorkshire fog, bird's-foot trefoil, white 

 clover, silverweed, and Crepis virens), and it is soon a 

 seaside meadow. It is difficult to trace the later stages, 

 for by the time that some of these weeds have effected 



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