De I. VNER VEW D Forest Trees of the Pacific Slope

FOREST TREES OF THE PACIFIC SLOPE.
Antelope Valley southward; West Walker River region eastward to within 8 miles of
Bridgeport; westward on river into mountains to Leavitt Meadow (7,150 feet) ; east
side of Bridgeport Valley to vest end of Mono Lake; Mono Basin and lower slopes west
of lake up slope on entrance to Bloody Canyon, also on east and southeast sides of
lake; south of Mammoth region on hills about Long Valley and between Long and Round
valleys. Inyo County: Hills at head of Round Valley; east slopes and summit of hills
north of Bishop, and opposite bottom slope of White Mountains (near Benton), here down
to upper edge of valley (about 5,500 feet altitude) ; northeast of Benton over plateau at
about 7,000 feet (between California and Nevada) ; south of Bishop higher on White
Mountains, forming belt on middle slope, and rising until lower limit on an east slope is
6,700 feet; west side Owens Valley forms a belt between 6,000 and 8,000 feet; Panamint
Range west of Death Valley, common In juniper belt on summit, and ranging (in basin
above Wild Rose Spring) on northwest slope of Telescope Peak, between about 6,400 and
9,000 feet. On Providence Mountains (west Colorado River) above 5,000 feet. On
southern Cross ranges at Tehachapi Pass (Tehachapi Mountains) down to 3,700 feet;
on Piute Mountains; near head of Caliente Creek above 4,000 feet; north part of Tehachapi
Pass (Mohave Desert side Tehachapi Basin) at 3,700 feet; lower slopes of Tehachapi
Mountain, Antelope Canyon. Tejon Mountains (between Castac Lake and Cuddys
Peak) in Cudahay Canyon; at Tejon Canyon and on hilts near Fort Tejon, at 4,000 to
6,000 feet. Occurs also on east base of Mount Pinos, in San Emigdio and Frazier mountains
at 2,600 to 7,900 feet, and on San Rafael Mountains, above 3,000 feet. Not on
southern mountains of Sierra Madre, but on Mount Islip and other north slopes westward
to Big Rock Creek; one tree known oiSfMount Lowe and another near mouth of Santa
Ana Canyon. In San Bernardino Mountains, abundant on north slopes, in northeastern
part, at 4,000 to 5,000-sometimes up to 7,000 feet, and extending westward to Mohave
River. From San Jacinto Mountains to Santa Rosa Mountains it occurs on desert slopes
above 4,200 feet, extending eastward to El Toro Mountain and Palm Springs on Colorado
Desert, here growing at an elevation as low as 2,000 feet. Summits of Coast Range near
Mexican boundary and Jacumba Spring (23 miles east of Campo) at 3,000 feet.
LOWER CALIFORNIA.-On east slopes (below 4,500 feet) from central table-lands to
plains of Colorado Desert and several miles south of Mexican boundary.
The detailed range of this pine east of the IPacific region will be dealt with in
a future publication.
OCCURRENCE.
Arid low mountain slopes, canyon sides, foothills, and mesas.
Requirements of soil moisture and quality of soil similar to those of associates, junipers
and chaparral, and are less than those of other conifers in its range. Commonly in
coarse, gravelly soils, shallow deposits overlying granite, limestone, or shale, often in
crevices of rocks.
Usually with other species, but frequently in pure, open stands over large areas.
Sparingly in chaparral; commonly with mountain mahogany, California juniper, oaks, tree
yuccas, or occasionally with straggling white fir and Jeffrey pine. Largest growth and
pure stands mainly at lower elevations.
CLIMATIC CONDITIONS.-Endures very great aridity, characterized by high temperature,
rapid evaporation, light precipitation, and little humidity. Rainfall varies from
about 16 inches in North to less than 5 inches In South. Snowfall, 4 feet in Sierras,
but absent or very slight over much of tree's range. Temperature ranges from -2° F. in
Sierras to 122' F. in Mohave Desert. In desert mountains of southeastern California
and Nevada it endures combined moisture and heat from February to May, extreme
drought from June to November, and extreme cold from December to January.
TOLERANCE.-Very intolerant throughout life; but seedlings appear to grow faster if
protected for several years from hot winds.
REPRODUCTroN.-Bears seed abundantly about every year. Wingless seeds fall near
tree. Largely eaten by birds and squirrels and collected by Indians and whites for food.
Exposed soil best seed bed. Reproduction usually very open or scattered-never dense.
Bristle-cone Pine.
Pinus aristata Engelmann.
DISTINGUISHING CHARACTERISTICS.
Bristle-cone pine, an alpine species, and only a straggler in the Pacific country,
Is known in the field as " fox-tail pine " and "hickory pine," but since these
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