FLORA OF YOSEMITE 
251 
oak. The chinquapin ( Castanopsis semper virens) , related to the 
eastern chinquapin ( Castanea pumila ), is a spreading shrub from 
one to eight feet high, with evergreen leaves, erect, staminate cat- 
kins several inches long and bearing white flowers. Small spiny 
burs cover the nuts. The species was common at Chinquapin, 
forming a dense growth. It was just in bloom about the last 
of August. 
In the flood plain of the stream and in some places in the valley 
there were great quantities of black cottonwood ( Populus tricho- 
carpa ), .a tree with somewhat variable' leaves, bright green above 
and rusty brown below. The trees of the valley are not large, 
generally from forty to eighty feet high, 1 J4 to -2 y 2 feet in di- 
ameter. There is only one other species of this genus in the 
region, namely the quaking aspen ( Populus tremuloides) . This 
is not what one would expect because in the Rockies P. tremu- 
loides is one of the most common species of the genus. I saw 
only a few trees, at the head of a little open somewhat boggy 
area near Crane Flat. It is reported at several other points at 
altitudes over 6,000 feet. 
The white alder ( Alnus rhombifolia) is common on the banks 
of streams through the Sierra canyons along with several species 
of willow {Salix) western azalea ( Rhododendron occidentals) 
with its beautiful white or pinkish corollas, the flowering dogwood 
( Cornus Nuttallii) and the common dogwood ( Cornus pubescens 
var Calif arnica) . The little mountain maple ( Acer glabrum) 
which is especially common near Mirror Lake and the higher 
slopes of the mountains, is an interesting mountain species. The 
big tree ( Sequoia Washingtoniana) occurs several thousand feet 
above the floor of the Yosemite valley. I visited only two groves ; 
the one near Crane Flat and the well known Mariposa grove in a 
glaciated region. The trees are found on the slope and in the 
little narrow valleys. There is in this region always an abundance 
of moisture from the abundant rainfall and the melting snow. 
The little valleys have fine springs. The big trees are associated 
with sugar pine, Alnus , Salix , Brig er on and other species of 
plants needing an abundance of moisture. The trees are either 
very old or very young ; there are no medium sized trees. These 
trees are California’s most marvelous production. Fortunately 
the Government is trying to save most of them. 
In a previous paragraph the statement was made that the floor 
of the valley is fairly uniform in character. At one time the open 
meadows were covered with an interesting lot of herbaceous 
plants. Severe grazing has destroyed many of the fine meadow 
