LOCATION ORLAND CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, nonacid, thermic Typic Xerofluvents
TYPICAL PEDON: Orland loam (nearly level at an elevation of 305 feet under annual grass-forb vegetation, uncultivated).
A11--0 to 1 inch; grayish brown (2.5Y 5/2) loam, dark grayish brown (2.5Y 4/2) when moist; weak medium platy structure; hard when dry, friable when moist, nonsticky and nonplastic when wet; few very fine roots; common very fine pores; slightly acid; abrupt, smooth lower boundary. (0 to 1 inch thick)
A12--1 to 11 inches; grayish brown (2.5Y 5/2) loam, dark grayish brown (2.5Y 4/2) when moist; essentially massive; hard when dry, friable when moist, slightly sticky and nonplastic when wet; abundant very fine roots; many very fine pores; some fragments have silvery sheen on faces; slightly acid; clear, smooth lower boundary; (6 to 12 inches thick)
C1--11 to 19 inches; grayish brown (2.5Y 5/2) stratified silt loam and fine sand, dark grayish brown (2.5Y 4/2) when moist with a few faint brown mottles in silt lenses; essentially massive but breaks to coarse subangular blocks with a silvery sheen on some faces; plentiful very fine roots; many very fine tubular pores; neutral; clear smooth lower boundary; 4 to 10 inches thick.
C2--19 to 39 inches; similar to above but loam texture with some gravel and a few roots; mildly alkaline; abrupt, smooth lower boundary; 10 to 30 inches thick.
D--39 + inches; grayish brown (2.5Y 5/2) very gravelly sand, dark grayish brown (2.5Y 4/2) when moist; structureless; loose dry and moist; slightly alkaline; many feet thick.
TYPE LOCATION: Approximately 4 miles northwest of Orland, California, near the SW corner of the SE1/4 of the SW1/4 of Sec. 6, T. 22 N., R. 3 W.
RANGE IN CHARACTERISTICS: Colors range from light brownish gray to grayish brown or gray. Textures are usually loam, silt loam, or fine sandy loam and are generally free of gravel although some gravelly or sandy strata may be present. The upper profile is slightly acid or neutral with the reaction increasing to neutral to moderately alkaline where calcareous. Profiles deeper than 30 inches to gravel are commonly slightly calcareous. The soils are usually moderately deep or deep to gravel but may be very deep or shallow.
COMPETING SERIES:
GEOGRAPHIC SETTING: Nearly level to very gently undulating recent flood plains and alluvial fans; channeled microrelief occurs in areas adjacent to actively eroding streams. The Orland soils occur at elevations below 1,250 feet in a dry subhumid, mesothermal climate having a mean annual precipitation of 15 to 25 inches with hot, dry summers and cool, moist winters; an average January temperature of about 44 degrees F.; an average July temperature of about 80 degrees F.; a mean annual temperature of about 61 degrees F.; and a frost free season of about 260 days.
GEOGRAPHICALLY ASSOCIATED SOILS: The Orland soils occur in the same general area as the Arbuckle, Cortina, and Wyo soils. They resemble the Columbia, Cortina, Elder, Molinos, Sorrento, Sycamore, Wyo, and Yolo soils. The Columbia soils developed in alluvium of mixed origin and are imperfectly drained, being mottled in the upper C horizons. The Cortina soils are gravelly throughout. The Elder soils developed in alluvium from siliceous shales, are dark grayish brown or dark gray, and usually are shaly and moderately fine textured. The Molinos soils developed in alluvium from basic igneous rocks, are moderately coarse textured, and usually dark grayish brown. The Sorrento soils are very similar to the Orland but developed in alluvium from relatively unmetamorphosed rock and contain little sericite. The Sycamore soils are mottled in the upper C horizons but otherwise resemble the Orland. The Wyo soils occur on slightly higher stream terraces or older flood plains; they have weakly developed textural B horizons. The Yolo soils have browner C horizons and are noncalcareous.
DRAINAGE AND PERMEABILITY: Well drained; runoff is slow; permeability is moderate. Areas not protected by levees are subject to overflow during periods of high rainfall. Water tables are normally below 6 to 8 feet, but may rise to 3 to 5 feet during periods of high stream flow if not flooded. Subsoil drainage is excessive for shallower phases.
USE AND VEGETATION: Moderately deep and deeper phases are well adapted to orchards, alfalfa, and irrigated field crops. Shallow depth phases or areas subject to flooding are used for grazing. Annual grasses and forbs with open to dense stands of valley oak, black walnut, and cottonwood trees.
DISTRIBUTION AND EXTENT: Recent flood plains and fans of major streams draining the foothills of the west side of the northern Sacramento Valley in California.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Soil Survey of the Colusa Area, California, 1907. Source of Name: Town of Orland in Glenn County, California.
REMARKS: Small stringers or bodies of gravelly Cortina soils are common inclusions in shallow depth phases and areas subject to flooding. This soil is classified as follows: USDA Yearbook: Alluvial soil; classification revision: 1.430; Univ. of Calif., Storie and Weir: Noncalcic Brown Alluvial, Profile Group I.
The activity class was added to the classification in February of 2003. Competing series were not checked at that time. - ET
OSED scanned by SSQA. Last revised by state on 01/60.