LOCATION KILAGA                  CA

Established Series
Rev. JR/WRR/DJE/AJT
01/2023

KILAGA SERIES


The Kilaga series consists of deep and very deep, well drained soils formed in alluvium from mixed rock sources. These soils are on terraces with slopes of 0 to 9 percent. The mean annual precipitation is about 20 inches and the mean annual temperature is about 62 degrees F.

TAXONOMIC CLASS: Fine, mixed, active, thermic Mollic Haploxeralfs

TYPICAL PEDON: Kilaga loam on a less than 1 percent slope in a cultivated field at 130 feet elevation (Colors are for dry soil unless otherwise noted).

Ap--0 to 10 inches; strong brown (7.5YR 5/6) loam, dark reddish brown (5YR 3/4) moist; massive; slightly hard, friable, nonsticky and slightly plastic; common very fine and fine vertical roots; many very fine tubular and interstitial pores; slightly acid (pH 6.5); abrupt smooth boundary. (5 to 10 inches thick)

A--10 to 19 inches; strong brown (7.5YR 5/6) heavy loam, reddish brown (5YR 4/4) moist; massive; hard, friable, slightly sticky and slightly plastic; few very fine tubular and interstitial pores; few thin clay films lining pores and bridging mineral grains; slightly acid (pH 6.5); clear wavy boundary. (5 to 9 inches thick)

Bt1--19 to 30 inches; reddish brown (5YR 4/4) clay loam, dark reddish brown (5YR 3/4) moist; moderate medium angular blocky structure; very hard, friable, sticky and plastic; few very fine random roots; common very fine and fine tubular and interstitial pores; many moderately thick clay films lining pores and on ped faces; neutral (pH 7.0); gradual wavy boundary. (8 to 15 inches thick)

Bt2--30 to 56 inches; reddish brown (5YR 4/4) clay matrix with reddish brown (2.5YR 4/4) ped faces, dark reddish brown (2.5YR 3/4) moist; moderate coarse prismatic and strong medium and coarse angular blocky structure; very hard, firm, sticky and plastic; few very fine random roots; few very fine tubular pores; continuous thick clay films on ped faces and lining pores; neutral (pH 7.3); gradual wavy boundary. (15 to 26 inches thick)

BCt--56 to 83 inches; reddish brown (5YR 4/4) sandy clay loam matrix with reddish brown (2.5YR 4/4) ped faces, dark reddish brown (5YR 3/4) moist; moderate medium angular blocky structure; very hard, friable, sticky and plastic; very few very fine random roots; common very fine and fine tubular and interstitial pores; many moderately thick clay films in pores and bridging mineral grains; moderately alkaline (pH 7.9).

TYPE LOCATION: Placer County, California; 1.5 miles southwest of Lincoln; 40 feet south and 600 feet east of the northwest corner of section 21, T.12 N., R.6 E. Lincoln Quadrangle

RANGE IN CHARACTERISTICS: Depth to duripan or stratified alluvium is 40 to 80 inches. The mean annual soil temperature is about 59 to 65 degrees F. and usually is not below 47 degrees F. at any time. The soil between depths of 5 to 15 inches is usually dry in all parts from May 15 until October 15, and is moist in some or all parts all the rest of the year.

The A horizon has dry color of 10YR 6/3, 5/3, 4/3, 4/4; 7.5YR 5/6 or 5/4 and moist colors of 10YR 3/4, 3/3, 3/2; 7.5YR 3/4; 5YR 3/4, 4/4. This horizon has more than 1.2 percent organic matter in the upper 4 inches and decreases with depth. Texture is clay loam, loam or sandy loam. Reaction is medium acid to neutral. The lower boundary is gradual with a gradual clay increase between the A and Bt horizon.

The Bt horizon has dry color of 10YR 5/4, 5/3; 7.5YR 5/4, 5/2; 5YR 6/4, 6/3, 5/4, 5/3, 4/4 and moist color of 10YR 4/4, 3/4; 7.5YR 4/4, 4/2; 5YR 3/4, 4/4; 2.5YR 3/4. Textures are heavy clay loam, silty clay loam, silty clay, sandy clay or clay. Clay content ranges from 35 to 50 percent. Structure is blocky or prismatic. Reaction is neutral to moderately alkaline. Manganese stains appear randomly in the Bt horizon.

COMPETING SERIES: These are the Argonaut, Conosta, Contra Costa, Fancher (T), Phipps and Trabuco series. The Argonaut, Conosta and Fancher soils have a paralithic contact at a depth of 20 to 40 inches. Contra Costa soils have a lithic contact at 20 to 40 inches. Phipps soils are on dissected hills and have 5 to 30 percent gravel throughout. Trabuco soils are on foothills and have 5 to 35 percent coarse fragment in the series control section.

GEOGRAPHIC SETTING: Kilaga soils are on nearly level to gently rolling terraces. Slopes range from 0 to 9 percent. Elevations are 50 to 200 feet. They formed in alluvium derived from mixed sources. The climate is subhumid with hot, dry summers and cool, moist winters. Mean annual precipitation is 15 to 25 inches. Average January temperature is 46 degrees F.; average July temperature is 79 degrees F.; mean annual temperature is 62 degrees F. The freeze-free season is 250 to 300 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cometa, Fiddyment, Kimball, Snelling and San Joaquin soils. The Cometa and Kimball soils have abrupt A-B boundaries. The Fiddyment and San Joaquin soils have duripans within 40 inches of the soil surface. The Snelling soils have fine-loamy argillic horizons. All are in similar positions.

DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; slow permeability. Some areas are subject to rare or occasional flooding.

USE AND VEGETATION: Used mostly for production of grain, irrigated pasture, orchard and field crops. Uncultivated areas are covered with annual grass, forbs and scattered oaks.

DISTRIBUTION AND EXTENT: Eastern edge of the Sacramento Valley, California. The soils are moderately extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES ESTABLISHED: Placer County (Western part), California, June 1974. Source of name from Kilaga Springs.

REMARKS: The activity class was added to the classification in January of 2003. Competing series were not checked at that time. - ET

Last revised by the state on 5/88.


National Cooperative Soil Survey
U.S.A.