LOCATION MCGREW             NE+CO
Established Series
Rev. SCB, LGR
09/2006

MCGREW SERIES


The McGrew series consists of somewhat poorly drained, moderately deep soils over gravelly sand formed in loamy alluvium over gravelly sand on flood plains. Slopes range from 0 to 2 percent. The mean annual precipitation is about 38 centimeters (15 inches), and the mean annual air temperature is about 9 degrees C. (48 degrees F.) at the type location.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, calcareous, mesic Aquic Ustifluvents

TYPICAL PEDON: McGrew loam with a slope of less than 2 percent in irrigated cropland. (Colors are for dry soil unless otherwise stated.)

Ap--0 to 20 centimeters (0 to 8 inches); light brownish gray (2.5Y 6/2) loam, dark grayish brown (2.5Y 4/2) moist; weak medium granular structure; slightly hard, friable; violent effervescence; slightly alkaline; abrupt smooth boundary.

A--20 to 25 centimeters (8 to 10 inches); light brownish gray (2.5Y 6/2) loam, dark grayish brown (2.5Y 4/2) moist; weak medium prismatic structure; slightly hard, friable; violent effervescence; slightly alkaline; clear smooth boundary. (Combined thickness of A horizon is 20 to 43 centimeters (8 to 17 inches) thick)

C--25 to 71 centimeters (10 to 28 inches); light gray (2.5Y 7/2) stratified very fine sandy loam, fine sandy loam, and loamy very fine sand, grayish brown (2.5Y 5/2) moist; many medium distinct yellowish brown (10YR 5/6) moist iron masses in matrix; massive; soft, very friable; slight effervescence; moderately alkaline; clear smooth boundary. (30 to 58 centimeters (12 to 23 inches) thick)

2C--71 to 203 centimeters (28 to 80 inches); light gray (2.5Y 7/2) gravelly coarse sand, light brownish gray (2.5Y 6/2) moist; common medium prominent reddish brown (5YR 4/4) moist iron masses in matrix; single grain; loose; slightly alkaline.

TYPE LOCATION: Scotts Bluff County, Nebraska; about 1.2 kilometers (3/4 mile) north and 0.4 kilometers (1/4 mile) west of McGrew; 418 meters (1372 feet) west and 386 meters (1267 feet) north of the southeast corner, sec. 26, T. 21 N., R. 53 W.

RANGE IN CHARACTERISTICS:
Thickness of the solum: 20 to 43 centimeters (8 to 17 inches)
Mixed coarse sand, gravelly sand, and gravelly coarse sand: 51 to 102 centimeters (20 to 40 inches)

A horizon:
Hue: 10YR or 2.5Y
Value: 5 to 7, 4 or 5 moist
Chroma: 1 to 3
Texture: typically loam, but ranges to very fine sandy loam, fine sandy loam, and sandy loam
Reaction: moderately to slightly alkaline

C horizon:
Hue: 10YR or 2.5Y
Value: 6 to 8, 4 to 6 moist
Chroma: 2 or 3
Texture: very fine sandy loam, fine sandy loam, sandy loam, and loamy very fine sand
Reaction: slightly to strongly alkaline

2C horizon:
Hue: 10YR or 2.5Y
Value: 5 to 7, 4 to 6 moist
Chroma: 2 or 3
Texture: coarse sand, gravelly sand or gravelly coarse sand
Gravel content: typically 15 to 35 percent but ranges 5 to 35 percent
Reaction: neutral to moderately alkaline

COMPETING SERIES: This is the Sanborn series.
Sanborn soils do not have gravelly sand within 60 inches.

GEOGRAPHIC SETTING:
Landford: nearly level and on flood plains
Slope: 0 to 2 percent
Parent Material: loamy alluvium over coarse sand and gravelly sand
Mean annual temperature: 8 to 11 degrees C. (47 to 51 degrees F.)
Mean annual precipitation: 36 to 46 centimeters (14 to 18 inches)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Gering, Haverson Las, Las Animas, and Platte soils.
Gering, Las, Las Animas, and Platte soils are on similar landscapes.
Haverson soils are fine-loamy, better drained and are higher on the landscape.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: somewhat poorly drained
Runoff: low
Saturated Hydraulic Conductivity: high above the 2C horizon and very high in the 2C
Seasonal high water table: 18 to 91 centimeters (1.5 to 3 feet)
Flooding: occasionally for brief durations

USE AND VEGETATION: A majority of the acreage is cultivated and irrigated.
The remainder is used for rangeland.
When cultivated the major crops are alfalfa, corn, sugar beets, dry edible beans, and potatoes.
Native vegetation the principal grasses are blue grama, switchgrass, western wheatgrass, little bluestem, and big bluestem.

DISTRIBUTION AND EXTENT: Western Nebraska. The series is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado

SERIES ESTABLISHED: Scotts Bluff County, Nebraska, 1968.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: 0 to 25 centimeters (0 to 10 inches) (Ap and A horizons)

Soils in the McGrew series were formerly mapped as a moderately deep phase of the Wann series. An alkali phase of the McGrew series has been recognized.

Modified format by LRM in 8/2006 to include metric conversion and change permeability to saturated hydraulic conductivity.


National Cooperative Soil Survey
U.S.A.