THE MOUNTAIN REGION OF CLEAR LAKE. 13 
near its upper end. There one finds Rumez persicarioides, 
Ludwigia palustris, the orange-colored flowers of Nymphaea 
advena, Brasenia peltata, Cinanthe Californica and 
Alisma Plantago aquatica. Some of the fertile valleys 
which border the lake shore and retreat into the hills are 
watered by surface and underground streams. Annuals and 
herbaceous perennials form extensive thickets four to ten 
feet high. There are such native plants as psoralea, epilo- 
bium and artemisia; such introduced weeds as sweet-clover, 
parsley and catnip. Supremely graceful oaks, eighty to one 
hundred feet in height, with slender trunks and only slightly 
diverging main branches, flourish in the rich well-watered 
soil. Over some of these the California grape-vine has hung 
its drapery of foliage, forming beautiful tall columns ten 
feet or more in diameter. 
North of Upper Lake a wagon-road crosses the ridge of 
Elk Mountain to the water-shed of the south fork of Eel 
River. In the pine forests grows Erigeron inornatus, 
Campanula prenanthoides and Brodiwa Ida-Maia. Many 
other plants are found only around mountain springs. Such 
are Lotus Torreyi, Agrimonia Eupatoria, Potentilla elata, 
Sidalcea Oregana, Hypericum Scouleri, Habenaria elegans, 
Gyrostachys gemmipara, and Lilium pardalinum. 
One finds throughout this region well-marked local plant 
districts with distinctive features, even in areas of similar 
topographical features. The high slopes about Uncle Sam 
Mountain are strikingly different from similar altitudes to 
the north of the lake, and as different, too, from the ridges 
of the Vaca Mountains, fifty miles southeastward. There 
was, however, little diversity in the plants of stream beds; 
everywhere on a circuit of three-hundred miles I found 
Eriogonum virgatum, Mentzelia levecaulis, Chrysopsis 
Oregana, Senecio eurycephalus, Nicotiana attenuata, Ver- 
bascum virgatum, Mimetanthe pilosa and Trichostema 
lacum. The flora of the foot-hills likewise changes 
little and is pretty constantly composed of Croton setigerus, 
