(d) Ice Plant, Sea Fig, or Mesembryanthemum (^Carpobvotus sp^. ) 

 These plants are common in the region southward from about latitude 39 N. 

 They are excellent stabilizers and easy to transplant, but are not very 

 effective as dune builders and cannot tolerate rapid sand burial. The 

 exotic and hybrid forms, which predominate in the region, are aggressive 

 and tend to exclude most other plants. Ice plant is susceptible to low 

 temperatures, risky where frost is possible, and vulnerable to traffic. 



It apparently requires fertilizer to remain healthy in the absence of 

 fresh sand. Unsightly dead patches are common in the intermediate zone 

 and these appear to be related to low nutrient supply. They do not appear 

 to be desirable plants to use on dunes. Ice plants crowd out other plants, 

 producing a rather monotonous, biologically uninteresting landscape. 



(e) Other Plants . Other plants in this region invade bare 

 sand near the sea and build foredunes (Wildemann, Dennis, and Smith, 1974). 

 The most prominent of these are yellow sand verbena (Ahrona latifolid) and 

 beach-bur {Ambrosia ahamissonis) . Sand verbena is salt tolerant but diffi- 

 cult to propagate. Beach-bur is easier to propagate but less tolerant of 

 salt spray and inundation by seawater. Practical procedures for field 

 planting are under study (Barbour, 1976). 



Most plants that are capable of growing near the foredune can only be 

 introduced after stabilization of the sand by pioneer species. These 

 species are essential for sand stabilization whenever the sand supply 

 declines. Seaside lupine [Lupinus littoralis) may be seeded into grass 

 stands and does well as a soil improver. As it dies down in winter it 

 is not an effective stabilizer. The beach peas {Lathyrus japoniaus 

 and L, littordlis) grow well in this zone. Native grasses that can be 

 seeded are seashore bluegrass [Poa maarantha') , native creeping red fescue 

 {Festuoa rubra) , sweet vernal {Anthoxanthwn adoration) , and velvet grass 

 {Holaus lanatus) . Farther back from shore, shrubs and trees are effec- 

 tive as stabilizers (Brown and Hafenrichter, 1962; Wiedemann, Dennis, 

 and Smith, 1974) . 



(5) South Pacific Region . Coastal dunes occur along this coast 

 but are not as extensive as in the North Pacific region (Zeller, 1962). 

 Sand activity declines sharply south of the Pt. Arguello, California, 

 region. Wind direction and the location of dunes near stream mouths are 

 similar to conditions in the North Pacific region. Because of lower wind- 

 speeds, bare sands are not as difficult to stabilize as in the Pacific 

 Northwest. However, the climate becomes warmer and drier farther south 

 and the perennial foredune grasses are not as well adapted to the climate. 

 This increases establishment hazards for dune-building plants. Also, the 

 coast is more heavily used by people so dune vegetation is generally in 

 poorer condition. 



(a) European Beachgrass . This grass has been planted suc- 

 cessfully on dunes along much of this coast. The moderating effect of 

 the sea apparently keeps pioneer zone temperatures within the tolerance 

 range for this species south to the Mexican border. Extensive plantings 

 were made in 1960 at Vandenberg Air Force Base, California, and these 



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