302 ANNUAL REPORT SMITHSONIAN INSTITUTION, 193 4 



are constantly guarded to rei^air the inroads of the sea during 

 storms. 



In southwestern France there is a region which consisted formerly 

 of alternating sand hills and marshes ill-fitted for agriculture and 

 sparsely populated. This area, called the " landes," lies between the 

 Gironde River and Bayonne. Beachgrass was planted and supple- 

 mented by brush fences to hold the sand. In due time a long barrier 

 dune was built up which protected the region behind. In the lee of 

 the barrier dune a forest of pines was produced. Since the reclama- 

 tion the conditions have so changed that the population has very 

 materially increased. 



In the Netherlands a line of dunes extends all along the coast of 

 the provinces of North Holland and South Holland. These are two 

 of the richest provinces in the kingdom, and it is very important to 

 prevent the encroachment of the sea upon the agricultural lands which 

 lie just back of the coast. Beachgrass plantings on the exposed sea- 

 ward side of the dunes prevent the sand from being blown inland, and 

 forests are planted on the lee side. 



Other important reclamation work by means of beachgrass has been 

 done in Denmark, especially on the north coast near Skagen, and 

 in Germany on the Baltic coast. Especially impressive is the work 

 done on the Kurische Nehrung in northeastern Prussia. This nar- 

 row sandpit (GO miles long) protects the harbor of the Kurisches 

 Haff , on the east side of which lies Memel. This harbor was formerly 

 endangered by the encroachment of the shifting sand from the dunes. 

 Here again the dunes were fixed with beachgrass, and later all except 

 the exposed sea slope was planted with trees. 



Our American species of beachgrass (Ammophila hreviligulata) , 

 found along the Atlantic coast as far south as North Carolina, and 

 around our Great Lakes, is similar to the European species and has 

 been used for holding dunes on Cape Cod and along Lake Michigan. 



Beachgrass not only has numerous and vigorous rhizomes but also 

 stems wdiich grow upward as the sand accumulates, never becoming 

 buried. 



COASTAL SALT MARSHES 



Salt or brackish marshes along the seacoast are made up largely of 

 rhizome-bearing grasses. The plants, of course, will not withstand 

 the battering of the surf, but in the quiet waters of bays and inlets 

 they thrive wherever the rise and fall of the tide is not too great, and 

 where the bottom is sand or mud. Large areas may be occupied by 

 a single species (notably species of Spartlmi, or cordgrass), the rhi- 

 zomes being so interlaced and so fully occupying the soil that no other 

 land of plant can gain a foothold. 



