Page 11 - macneill1947

8.

GEOGRAPHY

Inasmuch as a rather complete description of the

geography of the area is available in the literature, a brief

statement will suffice here.

Climate:

The climate is semi-arid, annual rainfall being about

17 inches. Precipitation ooours almost entirely during the

winter months. Most streams are intermittent. The mean annual

temperature is approximately 60• F.

Vegetation:

Yuoca, sage, manzanita and juniper grow in abundance on

the upper slopes. Sycamore and live oaks arEfl)resent along many

canyon bottoms, where there is more moi,sture.

Sharp ridges, south slopes, grassy meadows, and alluvium-

covered stream bottoms make up the only feasible traverse courses.

Most north slopes and box-canyon bottoms are impassable.

Physiography:

Ae compared with the rugged San Gabriel mountains to

the south, the Humphreys Station area is a low series of hills.

How~ver, elevations range up to 2400 feet with a maximum

relief of approximately 1,000 feet. Slopes as steep as 40° (!)

are common, and some steeper cliffs are found.

Structure does not appear to control the main drain-

age to fJD.Y great extent, although several subsequent streams

have out gorges along the traces of fault planes and fault

zones.