LOCATION GRASSYRIDGE        ID
Established Series
Rev. RJG/CLM
5/95

GRASSYRIDGE SERIES


The Grassyridge series consists of deep or very deep, somewhat excessively drained soils in calcareous eolian deposits on basalt plains. Slopes are 1 to 20 percent. Permeability is rapid. The average annual precipitation is about 10 inches and the average annual temperature is about 43 degrees F.

TAXONOMIC CLASS: Sandy, mixed, frigid Xeric Haplocalcids

TYPICAL PEDON: Grassyridge sand in rangeland on a southwesterly slope at an elevation of 5630 feet. When described on September 21, 1980, this concave site was dry to 20 inches and moist below. (Colors are for dry soils unless otherwise noted.)

A--0 to 8 inches; brown (10YR 5/3) sand, very dark grayish brown (10YR 3/2) moist; weak very fine granular structure; soft, very friable, many very fine and fine and common coarse roots; many very fine interstitial pores; slightly effervescent; mildly alkaline (pH 7.6); clear wavy boundary. (4 to 8 inches thick)

Bk1--8 to 28 inches; brown (10YR 5/3) fine sand, very dark grayish brown (10YR 3/2) moist; single grain; loose; common very fine and fine roots; many very fine interstitial pores; strongly effervescent; mildly alkaline (pH 7.8); gradual wavy boundary. (18 to 29 inches thick)

Bk2--28 to 49 inches; grayish brown (10YR 5/2) fine sand, dark gray (10YR 4/1) moist; single grain; loose; few very fine roots; common very fine interstitial pores; violently effervescent; moderately alkaline (pH 8.0); gradual wavy boundary. (18 to 22 inches thick)

C--49 to 60 inches; gray (10YR 5/1) fine sand, very dark gray (10YR 3/1) moist; single grain; loose; few very fine roots; few very fine interstitial pores; slightly effervescent; moderately alkaline (pH 7.9).

TYPE LOCATION: Fremont County, Idaho; approximately four miles north and 14 miles west of St. Anthony, about 1450 feet west and 225 feet south of the northeast corner of section 15, T.8N., R.38E.

RANGE IN CHARACTERISTICS:

Organic matter in upper 20 inches - less than 1 percent

Average annual soil temperature - 43 to 46 degrees F.

Summer soil temperature - approximately 60 degrees F.

Depth to calcic horizon - 4 to 8 inches

Clay in the control section - 2 to 10 percent

A horizon

Value- 4 or 5 dry

Chroma- 2 or 3 dry or moist

Structure - granular or single grain

Bk horizon

Value 5 through 7 dry, 3 through 5 moist

Chroma- 1 through 3 dry or moist

Calcium carbonate equivalent - 5 to 15 percent

C horizon

Value- 3 or 4 moist

COMPETING SERIES: There are no other series in the same family. The similar Malm and Matheson soils are in a coarse-loamy family.

GEOGRAPHIC SETTING: Grassyridge soils are on basalt plains and have formed in calcareous eolian deposits. Elevations range form 5250 to 5700 feet. Average annual precipitation is 9 to 12 inches. Average annual temperature is 41 to 44 degrees F. The frost-free season is 87 to 95 days. Winters are cool and moist, summers are dry and warm with occasional thunder showers.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Blacknoll (T), Juniperbute (T), and Wolverine soils. Blacknoll soils are 20 to 40 inches deep over basalt and are on adjacent slopes. Juniperbute soils lack a calcic horizon and are on adjacent slopes. Wolverine soils lack B horizons and are on stabilized sand dunes.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained. Slow to medium runoff. Rapid permeability.

USE AND VEGETATION: Irrigated cropland, rangeland and wildlife habitat. Crops include potatoes, barley, wheat and hay. Potential natural plant community includes basin big sagebrush, bluebunch wheatgrass, Indian ricegrass, needleandthread, Antelope bitterbrush and bluebunch wheatgrass.

DISTRIBUTION AND EXTENT: Southeast Idaho. These soils are not extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Fremont County, Idaho, 1989.

REMARKS: This revision changes the classification from Xerollic Calciorthids to Xeric Haplocalcids according to the 1994 edition of Keys to Soil Taxonomy. The remainder of the OSD has not been updated since 6/89.

Diagnostic properties include:

Particle-size control section - 10 to 40 inches. (Bk1 and part of the Bk2 horizons).

Ochric epipedon - 0 to 8 inches (A horizon).

Calcic horizon - 8 to 49 inches (Bk1, Bk2).


National Cooperative Soil Survey
U.S.A.