272 Part UI. Chapter 3. 
side according to the observations of the writer the redwood forest begins and 
stretches to the top, of the range which, at twenty miles from the sea, forms a 
barrier 2000 feet high, between the coast and the interior. 
Southern Coast Range Flora. Three mountains in the middle coast ranges 
of western central California are of interest in depicting briefly the characte- 
ristic mountainous flora of these parts of North America, Mount St. Helena 
(4343 feet, 1324 m), Mount Diablo (3849 feet, ı17ı m), Mount Hamilton 
(4209 feet, 1282 m) may be contrasted for this purpose‘). On account of its 
volcanic character (entire summit above 2300 feet covered with ash) and the 
scarcity of water, the number of species of plants found on Mount St. Helena 
is very small. Meager as the vegetation is in species, it would be even less 
were the mountain located in the inner instead of the middle coast range. 
Its situation is in a region of great annual rainfall, and the fogs hang about 
the mountain at intervals during the rainless season for a portion of the day 
for a period of several days to a week or more. The conditions on Mount 
Diablo are similar, distant sixty-seven miles. The vegetation of the mountain 
is, therefore, more rank than on Mount Hamilton which is not so favorably 
situated with regard to moisture. Notwithstanding the arid character of the 
summit of Mt. St. Helena, it possesses a few species characteristic of the humid 
coast region, or of the high Sierras and other elevated mountain ranges, such 
as, Pseudotsuga Douglasü, Cornus Nuttallii. Three species of Ceamolliks 
C. velutinus var. laevigatus, C. prostratus var. divergens, and C. folvosus, all 
found on Mt. St. Helena are not found in the inner north-coast range, nf yet 
on Mount Diablo. The vegetation of the summit is distinguished by the pre 
valence of shrubs of a limited number of species which completely mantle ie 
sides of the mountain above 2300 to 2500 feet. Arctostaphylos Manzanla 5 
very abundant, particularly at the highest elevation, and numerically outraf 
all other species. Garrya Fremonti, Xylotherınia montana, Rhamnus calıformiel | 
and Cranothus foliosus are common. Castanopsis chrysophylla also oCCUfS a 
Quercus chrysolepis and O. Wislisenii in scattered individuals. There un 
conspicuous lack of herbaceous species above 3000 feet, only such as Ayperica 
concinnum, Pedicularis densiflora, Monardella odoratissima and Zygaden 
Fremontii being found. | 
The Chemisal, or Chemise brush, covers slope after slope, 
and mile after mile with a low dense growth of a uniform blue green 
the shrub Adenostoma fasciculatum. A fern, Pellaea ornithopus, gYOW® in a 
Hill after bil 
det 
tufts on the hot slopes where in the chemisal some rocks have been b 
into fine debris. 
The barrier range mentioned above between the coast ranges and 
terior is diversified by masses of Pseudotsuga and species of QuercuS, 
the ir z 
thickeß: 
1) JErson, WirLıs L.: Vegetation of the Summit of Mt. St. Helena. Erythea vIl: 105 ” . 
1899. GREENR, E. L.: The . Vegetation of Mt. Diablo, Erythea I: 166. GREENE, BR ve 
Vegetation of the Summit of Mt. Hamilton. Erythea I: 80. These mountains are gr = 
order of their north-south position. ee 
