LOCATION MALMO NE+KSEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Aquertic Hapludalfs
TYPICAL PEDON: Malmo clay , on a southeast facing, 9 percent slope in cropland (Colors are for moist soil unless otherwise noted.)
Ap--0 to 6 inches; dark brown (7.5YR 3/2) clay; brown (7.5YR 4/3) dry; weak fine granular structure; hard, firm; few fine roots throughout; few fine discontinuous tubular pores; 3 percent rounded mixed-metamorphic and sedimentary gravel; slightly acid; clear smooth boundary. (4 to 9 inches thick)
Bt1--6 to 15 inches; 50 percent brown (7.5YR 4/2) and 50 percent yellowish red (5YR 4/6) clay, brown (7.5YR 5/4) and yellowish red (5YR 5/6) dry; moderate fine and medium subangular blocky structure; very hard, very firm; few fine roots throughout; few fine discontinuous tubular pores; discontinuous clay films on faces of peds; 3 percent rounded mixed-metamorphic and sedimentary gravel; many medium distinct light gray (10YR 7/2) iron depletions; neutral; clear smooth boundary.
Bt2--15 to 25 inches; 50 percent brown (7.5YR 4/2) and 50 percent yellowish red (5YR 4/6) clay, brown (7.5YR 5/4) and yellowish red (5YR 5/6) dry; moderate fine and medium subangular blocky structure; very hard, very firm; few fine roots throughout; few fine discontinuous tubular pores; discontinuous clay films on faces of peds; few fine and medium irregular carbonate concretions throughout; 3 percent rounded mixed-metamorphic and sedimentary gravel; many medium distinct grayish brown (10YR 5/2) iron depletions; slightly alkaline; clear smooth boundary.
Bt3--25 to 39 inches; yellowish red (5YR 5/8) clay; reddish yellow (5YR 6/8) dry; moderate medium angular blocky structure; very hard, very firm; discontinuous clay films on faces of peds; few medium irregular carbonate concretions; 3 percent rounded mixed-metamorphic and sedimentary gravel; many coarse prominent grayish brown (10YR 5/2) iron depletions; slightly alkaline; clear smooth boundary.
Bt4--39 to 43 inches; yellowish red (5YR 5/8) gravelly clay; reddish yellow (5YR 6/8) dry; weak medium angular blocky structure; very hard, very firm; discontinuous clay films on faces of peds; few medium irregular carbonate concretions; 18 percent rounded mixed-metamorphic and sedimentary gravel; many coarse prominent grayish brown (10YR 5/2) iron depletions; moderately alkaline; clear smooth boundary. (Combined thickness of the Bt horizon ranges from 28 to 60 inches.)
BC--43 to 54 inches; yellowish red (5YR 5/8) clay loam; reddish yellow (5YR 6/8) dry; weak medium angular blocky structure; hard, firm; few medium irregular carbonate concretions; 3 percent mixed-metamorphic and sedimentary gravel; many coarse prominent grayish brown (10YR 5/2) iron depletions; moderately alkaline; gradual smooth boundary. (6 to 20 inches thick)
C--54 to 72 inches; pale brown (10YR 6/3) loam; very pale brown (10YR 8/4) dry; massive; slightly hard, friable; 4 percent rounded mixed-metamorphic and sedimentary gravel; common coarse prominent yellowish red (5YR 5/6) soft masses of iron accumulation; slightly effervescent, moderately alkaline
TYPE LOCATION: Johnson County, Nebraska; about 3 miles east and 6 miles north of Tecumseh; located about 1000 feet west and 100 feet north of the southeast corner of sec. 25, T. 6 N., R. 11 E.; Tecumseh Northwest USGS quad; lat. 40 degrees 27 minutes 3 seconds N. and long. 96 degrees 7 minutes 34 seconds W., NAD 83
RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is wet from March though June; Udic moisture regime.
Mean annual soil temperature: 50 to 56 degrees F
Depth to argillic horizon: 4 to 9 inches
Depth to secondary calcium carbonate: 15 to 40 inches
Depth to redox concentrations: 35 to 90 inches
Depth to redox depletions: 4 to 9 inches
Depth to episaturation: 12 to 36 inches from March through June
Thickness of the solum: 40 to 72 inches
Particle-size control section (weighted average):
Clay content: 35 to 50 percent
Sand content: 20 to 50 percent
Rock fragments:
Content: 2 to 25 percent by volume
Size: gravel
A horizon:
Hue: 7.5YR or 10YR
Value: 2 to 4 and 3 to 5 dry
Chroma: 2 or 3
Texture: clay, clay loam or silty clay loam
Clay content: 35 to 46 percent
Reaction: moderately acid or slightly acid
Bt horizon:
Hue: 5YR to 10YR
Value: 3 to 5 and 4 to 6 dry
Chroma: 2 to 8
Texture: clay, clay loam and gravelly clay and less commonly sandy clay
Clay content: 35 to 50 percent
Rock fragments: 2 to 25 percent gravel
Reaction: slightly acid to slightly alkaline
BC and C horizons:
Hue: 2.5Y to 5YR
Value: 4 to 6 and 5 to 8 dry
Chroma: 2 to 8
Texture: clay loam and loam, but includes stratified clay, sandy loam or silty clay loam
Clay content: 20 to 45 percent
Rock fragments: 2 to 25 percent gravel
Reaction: neutral to moderately alkaline
COMPETING SERIES: These are the Armstrong, Clafork, Hoyleton, Mystic, Otoe, Pering, and Sunbury soils. Clafork, Hoyleton, Mystic and Pering soils do not allow carbonates in the solum. Otoe soils have less than 10 percent sand in the particle size control section. Sunbury soils do not allow carbonates above 45 inches.
GEOGRAPHIC SETTING:
Parent material: weathered glacial till
Landform: uplands
Slopes: 2 to 11 percent
Mean annual temperature: 50 to 56 degrees F
Mean annual precipitation: 28 to 34 inches
Frost-free period: 160 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Burchard,
Mayberry,
Morrill,
Wymore and
Yutan series. The Burchard, Mayberry, Morrill and Wymore soils have a mollic epipedon. Burchard and Morrill soils have less clay in the particle size control section.
The Burchard, Mayberry, and Morrill soils are on similar landscapes as the Malmo soils.
Wymore and Yutan soils contain less sand having formed in loess, and are usually higher on the landscape.
DRAINAGE AND PERMEABILITY: Moderately well drained, Medium runoff, Very slow permeability. A seasonal high water saturation zone is common at a depth of 1 to 3 feet in the spring.
USE AND VEGETATION: More than one-half of the areas of Malmo soils are cultivated. The principle crops are introduced grasses, grain sorghum and winter wheat. The remaining areas are in reseeded native grasses used for rangeland.
DISTRIBUTION AND EXTENT: Southeast Nebraska and possibly northeast Kansas; LRR M, MLRA 106; Moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Saunders county, Nebraska, 1992. The name is from a community in Saunders County.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: The zone from 6 to 43 inches. (All Bt horizons)
Ochric epipedon: The zone from 0 to 6 inches. (Ap horizon)
Argillic horizon: The zone from 6 to 43 inches. (Bt1, Bt2, Bt3, Bt4 horizons)
Redoximorphic features: In the zone from 6 inches on down. (All B and C horizons)
Vertic features: The presence of more than 35 clay at 6 to 43 inches. (Bt horizons)
Episaturation: The zone of saturation at 12 to 36 inches. (Bt horizons)
Remarks: These soils were previously mapped as Mayberry, severely eroded. These soils are assumed to have originally classified as Aquic Argiudolls. However, because of severe erosion, these soils no longer have a mollic epipedon. In addition, the part of the soil containing the most clay is now at or near the surface. These changes have a significant affect on the use and management of these soils.
lrr=M
date: 04/26/99
increased slopes to 12 percent due to Gage County update. sag