ilicifolia, Rosaceae), Mountain Mahogany (Cercocarpus betu- 

 loides, Rosaceae), and various species of manzanita (Arctostaphy- 

 los spp., Ericaceae) and California lilac (Ceanothus spp., Rham- 

 naceae). Also present are Scrub Oak (Quercus dumosd) and 

 Poison Oak {Rhus diversiloba, Anacardiaceae). In southern Cali- 

 fornia, additional species in Chaparral are Spanish Bayonet 

 (Yucca whipplei, Agavaceae), Laurel Sumac (Rhus laurina, Ana- 

 cardiaceae), and Sugar Bush (Rhus ovatd). 



The foregoing are the shrub species that are characteristic of 

 Chaparral. It should be pointed out, however, that numerous 

 other plant species occur in Chaparral. A tally of plants that com- 

 monly occur in Chaparral in California indicates that nearly 900 

 species of vascular plants occur in this community. About 240 of 

 these are woody plants, most of which are shrubs; well over 300 

 are annual or biennial herbs; an equal number of perennial herb 

 species is present. The largest plant famiUes present are the Com- 

 positae (sunflowers) with over 90 species in Chaparral, Scrophu- 

 lariaceae (figworts) with nearly 70 species, and Gramineae 

 (grasses), Leguminosae (legumes), Hydrophyllaceae (waterleafs), 

 Labiatae (mints), Ericaceae (heaths), and Liliaceae (lilies) with 

 between 30 and 40 species of each. Thus, the list of characteristic 

 species in any plant community is a gross oversimplification of 

 what one can expect to find there. The species that have been 

 chosen as typical, however, generally are widely distributed, 

 common, and conspicuous in these plant communities, and be- 

 cause of these traits they are listed in preference to less conspicu- 

 ous species, less widely distributed ones, or ones with less of an 

 ecological fidelity. 



Chaparral occurs in areas with wet, mild winters and long, dry, 

 hot summers. Average annual rainfall ranges from about 1 5 inches 

 to 25 inches (38 to 64 cm). However, summer rainfall accounts 

 for less than 20 percent of the annual total rainfall. Soils occupied 

 by Chaparral are often gravelly or sandy, shallow, and have a low 

 water-holding capacity. The distribution of Chaparral in California 

 is a "spotty" one which shows no clear geographic coherence. A 

 probable explanation for this is that Chaparral often occurs in an 

 area having a climate that would lead one to expect a woodland 

 community, but because of the local unfavorable soil situation. 



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