1927
1999
Side by side comparison
Map
Data Sheet
DRY VALLEY NEAR CASA COLORADO ROCK
General Description: This site is on an escarpment overlooking Hatch Wash
approximately 1.5 miles southwest of Casa Colorado Rock. It is located about .4
mile west of an oil pipeline. The view is north across public lands administered
by the Bureau of Land Management.
Soils: Soils at this site are classified as Begay-rock outcrop-Mido
complex. These soils occur on structural bench escarpments along drainage ways.
Specific soils at the exact site tend toward a rock outcrop-Mido loamy fine
sand. Soils here do not reach typical Mido soil depths as evidenced by the rock
outcrops appearing in the photographs. It is estimated that soil depths in the
area from the immediate foreground to the top of the escarpment range from 6 to
40 inches. Mido soils have rapid permeability and low water supplying
capability.
Precipitation: Average annual precipitation at this location ranges from
10 to 12 inches.
Legal Description: NE1/4SW1/4 Section 19 T.30S., R.24E.
COMPARISON: Overall plant densities appear to have increased here, but
shrub frequency has decreased in favor of grass species. The most striking
difference, however, between the 1927 and 1999 images is the health and vigor of
the plant community as a whole which has resulted in a much improved ground
cover situation. Some of the plant species present include juniper, sagebrush,
fourwing saltbush, winterfat, snakeweed, Indian ricegrass, curlygrass, blue
grama, needle and thread grass, cheatgrass, and threeawn.
Original:
Date: 1927 (- A)
Photographer: A.A. Baker
Source: U.S. Geological Survey, Denver, Colorado
Photograph Number: Baker No.216
Retake:
Date: May 13, 1999 (- B)
Photographer: Earl Hindley
Source: San Juan County
