LOCATION MORA               MN+WI
Established Series
Rev. RLB-JFG-KDS-AGG
09/2006

MORA SERIES


The Mora series consists of very deep, somewhat poorly drained soils that formed in loamy till on drumlins and moraines. These soils have a densic contact at 40 to 60 inches. Slope ranges from 0 to 6 percent. Mean annual precipitation is about 28 inches. Mean annual air temperature is about 43 degrees F.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, frigid Aquic Glossudalfs

TYPICAL PEDON: Mora fine sandy loam, on a convex slope of 3 percent, in a cultivated field. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 8 inches; dark brown (10YR 3/3) fine sandy loam, grayish brown (10YR 5/2) dry; weak fine granular structure; friable; about 1 percent gravel; moderately acid; clear smooth boundary. (3 to 9 inches thick)

E--8 to 12 inches; brown (10YR 5/3) fine sandy loam, very pale brown (10YR 7/3) dry; weak medium platy structure; friable; common fine and medium distinct yellowish brown (10YR 5/6) Fe concentrations; about 1 percent gravel; moderately acid; clear wavy boundary. (0 to 12 inches thick)

B/E--12 to 17 inches; about 70 percent brown (7.5YR 4/4) fine sandy loam (Bt); about 30 percent brown (10YR 5/3) fine sandy loam (E), 10YR 7/2 dry; weak fine and medium subangular blocky structure; friable; few fine distinct strong brown (7.5YR 4/6) and common fine and medium distinct yellowish brown (10YR 5/6) Fe concentrations; about 3 percent gravel; moderately acid; clear wavy boundary. (2 to 10 inches thick)

Bt1--17 to 30 inches; reddish brown (5YR 4/4) fine sandy loam; weak fine and medium subangular blocky structure; friable; common distinct discontinuous dark reddish brown (5YR 3/3) clay films on faces of peds; common fine and medium distinct brown (7.5YR 5/2) Fe depletions and common medium distinct yellowish red (5YR 5/6) Fe concentrations; about 5 percent gravel; moderately acid; clear wavy boundary.

Bt2--30 to 36 inches; reddish brown (5YR 4/3) fine sandy loam; weak medium platy structure; friable; few distinct discontinuous dark reddish brown (5YR 3/3) clay films on bottoms of plates; few medium faint reddish brown (5YR 5/3) Fe depletions and few medium distinct yellowish red (5YR 4/6) Fe concentrations; about 5 percent gravel; slightly acid; clear wavy boundary. (Combined thickness of the Bt horizon is 8 to 35 inches.)

BC--36 to 46 inches; dark reddish brown (5YR 3/4) fine sandy loam; few fine and medium faint reddish brown (5YR 5/3) Fe depletions and few medium distinct yellowish red (5YR 4/6) Fe concentrations; moderate thick platy structure; firm; few faint brown (7.5YR 4/4) clay films on bottoms of plates; about 5 percent gravel and 2 percent cobbles; slightly acid; gradual wavy boundary. (0 to 15 inches thick)

BCd--46 to 80 inches; dark reddish brown (5YR 3/4) fine sandy loam; moderate very coarse and extremely coarse prismatic structure parting to moderate fine and medium platy, few 2 to 3 millimeter oblique fractures 0.5 to 3.0 feet apart; very firm; few faint reddish brown (5YR 5/3) Fe depletions and yellowish red (5YR 4/6) Fe concentrations on fracture faces; about 5 percent gravel and 2 percent cobbles; slightly acid.

TYPE LOCATION: Mille Lacs County, Minnesota; about 11 miles north of Bock; located about 100 feet north and 1,200 feet west of the southeast corner of section 14, T. 40 N., R. 26 W.; USGS Milaca NE topographic quadrangle; lat. 45 degrees 57 minutes 05 seconds N. and long. 93 degrees 33 minutes 10 seconds W., NAD 83.

RANGE IN CHARACTERISTICS: Depth to densic material is 40 to 60 inches. Rock fragment content ranges from 1 to 15 percent by volume throughout the profile. The argillic horizon has 8 to 18 percent clay. Stony and very stony surface phases are recognized.

The A or Ap horizon has hue of 10YR or 7.5YR, value of 2 or 3, and chroma of 1 to 3. It is fine sandy loam, sandy loam, very fine sandy loam, loam or silt loam. It is strongly acid to slightly acid.

The E horizon has hue of 10YR or 7.5YR, value of 4 or 5, and chroma of 2 or 3. Dry hue is the same, value is 6 or 7, and chroma is 2 or 3. It is fine sandy loam, sandy loam, very fine sandy loam or silt loam. It is strongly acid to slightly acid.

The E/B or B/E horizon has properties similar to the E and Bt horizon respectively. The E part has properties that qualify for albic material.

The Bt horizon has hue of 5YR or 7.5YR, value of 3 to 5, and chroma of 3 or 4. It is fine sandy loam, sandy loam, or loam. It is strongly acid to slightly acid. Bulk density ranges from 1.50 to 1.70 gm/cc. The base status is greater than 60 percent.

The BC horizon has hue of 5YR or less commonly 7.5YR, value of 3 to 5, and chroma of 3 or 4. It is fine sandy loam or sandy loam. It is moderately acid to neutral. Moist bulk density ranges from 1.65 to 1.80gm/cc.

The BCd horizon has hue 5YR or less commonly 7.5YR, value of 3 to 5 and chroma of 3 or 4. It is fine sandy loam or sandy loam. Clay content averages more than 7 percent. It is moderately acid to neutral. Moist bulk density ranges from 1.80 to 2.0 gm/cc. It is considered to be densic material. Macro structure is common in the form of fractures.

COMPETING SERIES: These are Brennyville, Fallcreek, Glendenning, Hatley, Magnor, Magroc, Oesterle, Plover, Rosy, and Stinnett series. Fallcreek, Hatley, Magroc, Oesterle, Plover and Rosy soils do not have densic materials within the series control section. Brennyville, Hatley and Magnor soils have a silt loam mantle over 12 inches thick. Glendenning soils have base saturation below 60 percent in some part of the argillic horizon. Magroc soils have a lithic contact at a depth of 40 to 60 inches. Oesterle soils have sandy and gravelly outwash within a depth of 40 inches. Plover and Rosy soils are stratified in the lower part of the series control section. Stinnett soils average less than 7 percent clay in the dense till.

GEOGRAPHIC SETTING: These soils are on nearly level to gently sloping drumlins or moraines. Slope ranges from 0 to 6 percent. Mora soils formed in noncalcareous, Superior lobe dense loamy till of Late Wisconsinan Age. Mean annual air temperature ranges from 37 to 45 degrees F. Mean annual precipitation ranges from 24 to 33 inches. Frost-free period ranges from 90 to 145 days. Elevation ranges from 670 to 1,450 feet above sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Adolph, Brennyville, Cebana, Giese, Milaca, Parent, and Ronneby soils, which form a drainage sequence with the Mora soils. The very poorly drained Adolph and Giese soils are in depressions. The somewhat poorly drained Brennyville soils are on similar landscape positions as the Mora soils. The poorly drained Cebana, Parent, and Ronneby soils are on flats and swales. The moderately well drained Milaca soils are on steeper and higher lying landscape positions.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained. Surface runoff is negligible to medium. Saturated hydraulic conductivity is 4.23 to 42.34 micrometers per second (.6 to 6 inches per hour) in the upper part and .01 to .42 micrometers per second (.0015 to .06 inches per hour) in the dense till. This soil has perched season high saturation at depths as high as 0.5 foot during April through May in years of normal precipitation.

USE AND VEGETATION: About one-half of these soil areas are forested. The remaining areas are cleared and used for pasture or are cropped to corn, oats, and hay. Native vegetation is mixed deciduous forest or mixed deciduous-coniferous forest.

DISTRIBUTION AND EXTENT: MLRA 90, mostly in east-central Minnesota. This series is moderately extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota.

SERIES ESTABLISHED: Benton County, Minnesota, 1970. Reclassified and moved to Mille Lacs County, Minnesota, 2002.

REMARKS: Diagnostic horizons and features recognized in this pedon include: ochric epipedon - the zone from the surface to 12 inches (A and E horizons); albic horizon - the zone from 8 to 12 inches (E horizon); glossic horizon - the zone from 12 to 17 inches (B/E horizon); argillic horizon - the zone from 12 to 36 inches (B/E, Bt1, and Bt2 horizons); densic contact - the zone beginning at 46 inches (BCd horizon); aquic subgroup - low chroma redoximorphic features in upper 10 inches of the argillic horizon. Aquic condition based on a presumed positive reaction with alpha-alpha dipyridyl at some time during the year in 6 out of 10 years. This red parent material does not produce reduced soil colors typical of other parent materials. Base saturation above 60 percent in all parts of the argillic horizon. The dense till has repetitive fracturing that affects water movement and root penetration.

This soil was previously classified as a coarse-loamy, mixed, superactive, frigid Aquic Hapludalfs. Field investigations have shown a predominance of a glossic horizon in this soil.


National Cooperative Soil Survey
U.S.A.