NOTES ON THE ECOLOGY OF SAND DUNE PLANTS 



EDWARD B. COUCH 



University of Southern California, Los Angeles, Cal. 



The dunes studied are those at Peck's Manhattan Beach, between 

 Redondo and Venice, Cahfornia. They are practically undis- 

 turbed, and therefore lend themselves readily to safe investigation 

 of their flora. These dunes rise to a height of about 150 feet above 

 sea level in a horizontal distance of three-quarters of a mile and 

 descend abruptly 75 feet in about 100 feet of hoi'izontal distance. 

 The physiography is referred to as windward slopes, as summits, 

 or as leeward slopes the configuration of the dunes having been 

 determined by the sea winds. 



Quadrat counts covering the dunes were made in Alarch 1913, 

 each quadrat being 10 meters square. 



Quadrat No. 1 



One-quarter mile from the sea on the windward slope 



Gaertneria hipinatifida 30 



Eriogonum parvifolium 12 



Abronia umbellata 11 



Lotus Junceus 1 



Lupinus Chamissonis 1 



Quadrat No. 2 



One-half mile from the sea on windward slope, a ridge 



Gaertneria hipinatifida 12 



Lupinus Chamissonis 4 



Abronia umbellata 3 



Quadrat No. 3 



One-half mile from sea, windward slope on edge of a blow-out 



Gaertneria hipinatifida 17 



Abronia umbellata 7 



Lotus Junceus : 5 



Lupinus Chamissonis 1 



Eremocarpus setigerus 1 



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