LOCATION ROYSTONE ID
Established Series
Rev. LMR/TWP
12/2022
ROYSTONE SERIES
The Roystone series consists of deep, moderately well drained soils that formed in alluvium from mixed basaltic and intrusive acid igneous rock sources under somewhat poorly or poor drainage conditions. Roystone soils are on stream bottoms, low terraces, and alluvial fans and have slopes of 0 to 5 percent. The mean annual precipitation is about 12 inches and the mean annual air temperature is about 49 degrees F.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Calcic Pachic Argixerolls
TYPICAL PEDON: Roystone loam, cultivated. (colors are for dry soil unless otherwise noted.)
A1p--0 to 5 inches; dark gray (2.5Y 4/1) loam, black (2.5Y 2/1) moist; weak medium platy structure parting to moderate fine granular; slightly hard, friable, slightly sticky and slightly plastic; common fine roots; common very fine pores; neutral (pH 7.1); clear smooth boundary. (4 to 8 inches thick)
A12--5 to 10 inches; dark gray (2.5Y 4/1) loam, black (2.5Y 2/1) moist; moderate fine and very fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; common fine roots; common very fine pores; neutral (pH 7.1); clear smooth boundary. (4 to 12 inches thick)
B1t--10 to 15 inches; dark gray (2.5Y 4/1) clay loam, black (2.5Y 2/1) moist; weak medium prismatic structure parting to moderate fine angular blocky; hard, firm, sticky and plastic; common fine roots; few very fine pores; many thin clay films on surfaces of peds; neutral (pH 7.2); gradual smooth boundary. (4 to 8 inches thick)
B2t--15 to 23 inches; gray (2.5Y 5/1) clay loam, very dark grayish brown (2.5Y 3/1) moist; dark gray (2.5Y 4/1) coating, very dark gray (2.5Y 3/1) moist; weak medium prismatic structure parting to moderate fine angular blocky; hard, firm, sticky and plastic; common fine roots along vertical surfaces of peds; few very fine pores; continuous thin to thick clay films on surfaces of peds; slightly alkaline (pH 7.6); clear smooth boundary. (6 to 12 inches thick)
B3tca--23 to 36 inches; gray (2.5Y 5/1) clay loam, very dark grayish brown (2.5Y 3/1) moist; weak medium prismatic structure parting to moderate fine subangular blocky; hard, firm, sticky and plastic; few roots; common very fine pores; few thin clay films; common 1/8 inch lime veins; moderately alkaline (pH 8.2); gradual smooth boundary. (10 to 20 inches thick)
Cca--36 to 60 inches; gray (2.5Y 5/1) loam, very dark grayish brown (2.5Y 3/2) moist; weak fine and very fine subangular blocky structure; slightly hard, friable, sticky and slightly plastic; few fine roots; common very fine pores; slightly calcareous; moderately alkaline (pH 8.0).
TYPE LOCATION: Gem County, Idaho; about 10 miles north of Emmett; 1,500 feet north of the center of sec. 36, T.8N., R.2W.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is about 47 degrees to 53 degrees F. The soil is usually moist, but is dry between depths of 4 and 12 inches for 45 to 70 consecutive days in late summer and early fall. The depth to calcareous material ranges from 18 to 30 inches. the solum is about 30 to 45 inches thick and is neutral or mildly alkaline. Rock fragments ranges up to 10 percent by volume, and consist mostly of fine pebbles.
The A horizon has value of 3 through 5 dry, 2 or 3 moist, and chroma of 1 or neutral dry and moist.
The Bt horizon has hue of 2.5Y or 10YR, value of 3 through 5 dry, 2 or 3 moist, and chroma of 1 or 2 dry and moist. This horizon is mainly clay loam, but ranges to silty clay loam or heavy loam and averages 18 to 35 percent clay. Thin lenses of coarser material are in some pedons. The accumulation of calcium carbonate in the lower part is weak or moderate.
The Cca horizon is slightly or moderately calcareous, and is stratified with layers of coarser material in most pedons.
COMPETING SERIES: These are the
Crookston,
Newell and
Yergenson series. Crookston soils have calcic horizons and loam or silt loam argillic horizons. Newell soils have chroma of 2 or 3 in the A horizons, and depth to carbonates is 30 to 43 inches. Yergenson soils are loamy-skeletal.
GEOGRAPHIC SETTING: Roystone soils are on stream bottoms, low terraces, and alluvial fans and have slopes of 0 to 5 percent. Elevation are 2,500 to 3,500 feet. The climate has dry warm summers with cold moist winters. Mean annual precipitation of 11 inches, mean annual summer temperature is 69 degrees to 73 degrees F., and the mean annual temperature is 46 degrees to 52 degrees F. Frost-free season is about 130 to 165 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Bissell,
Harpt,
Newell and
Yergenson soils. Bissell soils have a mollic epipedon less than 20 inches thick and an aridic moisture regime. Harpt soils do not have an argillic horizon.
DRAINAGE AND PERMEABILITY: Moderately well drained (soil may have formed under somewhat poor or poor drainage); slow runoff; moderately slow permeability.
USE AND VEGETATION: Used mainly for production of nonirrigated wheat, barley, alfalfa hay and as rangeland. Vegetation is bluebunch wheatgrass, wildrye, big sagebrush and related herbaceous plants.
DISTRIBUTION AND EXTENT: Dissected stream valleys of southwestern Idaho. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Gem County, Idaho, 1957.
National Cooperative Soil Survey
U.S.A.