FLORA OF THE PACIFIC COAST 



are to be seen extensive fields of Eschscholtzia and 

 Platystemon. Those who journey still farther south- 

 ward will find all of the foothill slopes around the 

 Santa Clara Valley teeming with attractive and inter- 

 esting species. To the east and north of San Fran- 

 cisco Bay the hill districts form the chief attraction. 

 Here will be found Brodiaea, Chlorogalum, Sidalcea, 

 Orthocarpus, Castilleia, Wyethia, Nemophila, Lathy- 

 rus, and many other genera of showy or othersyise 

 interesting seed plants. Passing northward into 

 Oregon and Washington these formations become of 

 less and less importance. There the coniferous for- 

 ests predominate. 



The Chaparral Flora (Upper Sonoran zone). 

 Chaparral is a term applied in the West to any low 

 and shrubby growth regardless of the species of 

 which it may be composed. Its individuals are lit- 

 erally the "little chaps" as contrasted with the for- 

 est trees. It corresponds to the maqui of the Medit- 

 erranean region, and to the scrub of Australia. 

 Although it occurs also in other life zones, chaparral 

 is with us preeminently characteristic of the Upper 

 Sonoran, or, as it is often called, the foothill or 

 chaparral belt. 



Our Upper Sonoran chaparral is strongly xero- 

 phytic in character. The root system is well devel- 

 oped and in many cases harbors bacteria the presence 

 of which is presumably beneficial; the branching is 

 profuse and intricate; the usually narrow evergreen 

 leaves are heavily cutinized, often covered with 

 tomentum (e. g., Artemisia californica, Eriodictyon 

 tomentosum, Malvqstrum of several species), or they 

 may assume a vertical position (Arctostaphylos, Den- 

 dromecon). Often the herbage is strongly resinous 

 (Ericqmeria, Baccharis) or coated with a gummy or 

 wax-like layer (Eriodictyon calif ornicum). 



In order to observe the many peculiarities of our 

 shrubby vegetation it is necessary to travel only a 

 short distance from the cities and towns usually 

 visited, for chaparral abounds in almost every dis- 

 trict except along the northwest coast. In the imme- 

 diate vicinity of San Diego it is restricted chiefly to 

 northerly slopes of the arroyos, but here are found 

 Mexican species of the Lower Sonoran zone which 

 do not occur much farther north. Such are Viguiera 

 laciniatq and Encelia farinosa, both yellow-flowered 

 Composites, the latter ranging north to San Bernar- 

 dino. Along the foothills from this last-named city 

 to Los Angeles is found a broad chaparral belt in 

 which the chamisal (Adenostoma californica) is 

 very prominent. This narrow-leaved Rosaceous 

 shrub is one of the most abundant in the whole 



150 



