northern California exceeds 350 days. Because of the tempering 

 effect of the adjacent ocean, diurnal as well as seasonal tempera- 

 ture fluctuations are relatively small. Summers are cool and win- 

 ters are relatively warm. 



Despite the relatively benign climatic conditions outlined 

 above, the environment of the Coastal Strand plant community 

 is a harsh one. This may explain why there are so few plant spe- 

 cies that occur in this community. The community is subjected 

 to strong winds during much of the year, and these carry salts 

 that are deposited on the plants and the soil. Because of these 

 salt-laden winds and occasional high tides during winter storms, 

 the sand occupied by the plants has a high concentration of sea 

 salts. Besides being salty, the sand is often very unstable and 

 blown about by the winds. The level of plant nutrients is gen- 

 erally very low; from a nutritional standpoint these sands are in- 

 fertile. Furthermore, during summer months the surface of the 

 sand may become extremely hot, to the extent that it is very 

 uncomfortable to the human touch. 



Although the plant species that occur in the Coastal Strand are 

 taxonomically unrelated, many of them share a number of simi- 

 lar adaptive characteristics. For example, many of the plants in 

 this community are prostrate and have creeping stems that hug 

 the sand. In some species, these stems may produce roots at 

 the nodes and eventually form a large colony derived from a 

 single individual. Sexual reproduction of some of the perennial 

 species may be relatively rare, perhaps because of the great diffi-- 

 culties that seedlings have in becoming established in the con- 

 tinually shifting and generally inhospitable sands. Also, many 

 Coastal Strand plants have grayish foliage; this is probably an 

 adaptation to the frequent extreme daytime heat to which these 

 plants are subjected and undoubtedly serves to reflect heat from 

 the plant and thus reduce the temperature of internal tissues. 

 Plants in this community are frequently succulent and may have 

 sufficiently high salt concentrations in their tissues to be detecti- 

 ble to the human taste. Possibly this succulence is an adaptation 

 to the occasional dry periods to which strand plants are sub- 

 jected, and it may also enable these plants to take in water whose 

 salt content would dehydrate most non-succulent plants of 



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