LOCATION KIRK OREstablished Series
TAXONOMIC CLASS: Ashy-pumiceous, glassy, nonacid Typic Cryaquands
TYPICAL PEDON: Kirk medial loam, irrigated pasture. (Colors are for moist soil unless otherwise noted.)
A1--0 to 1 1/2 inches; very dark gray (10YR 3/1) medial loam, gray (N 5/) dry; massive; soft, friable, nonsticky and nonplastic; many very fine roots; neutral (pH 7.2); abrupt smooth boundary. (0 to 3 inches thick)
A2--1 1/2 to 5 inches; black (10YR 2/1) medial loam, gray (N 5/) dry; weak thin platy structure parting to weak very fine granular; soft, friable, slightly sticky and slightly plastic; common very fine roots; common very fine tubular pores; 5 percent gravel-size pumice; neutral (pH 6.8); clear smooth boundary. (3 to 7 inches thick)
A3--5 to 9 inches; very dark brown (10YR 2/2) medial loam, gray (2.5Y 5/1) dry; weak medium subangular blocky structure parting to weak very fine granular; soft, friable, slightly sticky and slightly plastic; common very fine roots; common very fine tubular pores; 5 percent gravel-size pumice; slightly acid (pH 6.5); gradual smooth boundary. (4 to 10 inches thick)
AB--9 to 15 inches; very dark gray (10YR 3/1) paragravelly ashy sandy loam, gray (10YR 6/1) dry; single grained; very friable, slightly sticky and nonplastic; common very fine roots; many very fine pores; 15 percent gravel-size pumice; slightly acid (pH 6.5); gradual smooth boundary. (6 to 18 inches thick)
BC--15 to 60 inches; very dark gray (10YR 3/1), gray (10YR 6/1) very paragravelly ashy loamy sand, gray (10YR 6/1) dry; many dark grayish brown (10YR 4/2) redox concentrations, single grained; very friable; few very fine roots; many very fine pores; 40 percent gravel-size pumice and 10 percent cobble-size pumice; neutral (pH 6.7).
TYPE LOCATION: Klamath County, Oregon; about 1/4 mile west of the town of Fort Klamath; 1,750 feet west and 200 feet south of the NE corner of section 21, T.33S., R.7-1/2E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 35 to 40 degrees F., the mean summer soil temperature is 40 to 45 degrees F. and the mean winter soil temperature is 32 to 35 degrees F. The soils are saturated most of the year. Chroma, moist, is 2 or less to a depth of 20 inches or more. The mineral fraction is ash and pumice. Depth to the very paragravelly or extremely paragravelly pumice and ash layers ranges from 14 to 38 inches. The transition between the upper part of the particle-size control section (A horizons) and the lower part (AB horizon) is gradual or clear. The solum commonly is neutral or slightly acid but ranges to very strongly alkaline in the surface horizon.
The A horizon has hue of 10YR, neutral, or 2.5Y, value of 2 or 3 moist, 4 or 5 dry, and chroma of 1 or 2 moist, 0 to 1 dry. It has 0 to 15 percent pumice of gravel size. It has 12 to 20 percent 15-bar moisture based on an air-dried sample. Phosphate retention is 25 to 35 percent. It has 40 to 70 percent glass. Acid oxalate extractable aluminum plus one-half the iron is 0.4 to 1.0.
The AB horizon has value of 3 or 4 moist, 5 or 6 dry, and chroma of 0 or 1 moist, 1 or 2 dry. It is ashy sandy loam or ashy loamy sand with 15 to 35 percent gravel-size pumice. It hs 8 to 12 percent 15 bar water on dried samples, 60 to 90 percent glass, phosphate retention of 25 to 35 percent and acid oxalate extractable aluminum plus one-half the iron of 0.4 to 1.0.
The BC horizon has value of 3 through 6 moist, 6 through 8 dry, and chroma of 1 through 4 moist, 2 or 3 dry. It is ashy loamy sand, ashy sand, or ashy coarse sand and has about 30 to 50 percent pumice of gravel size and 5 to 25 percent pumice of cobble size. It has 15-bar moisture of 3 to 8 percent based on an air-dried sample.
COMPETING SERIES: These are the Wickiup series. The Wickiup soils have an ochric epipedon and lack the medial loam surface layers.
GEOGRAPHIC SETTING: Kirk soils are on flood plains in basins. Elevations are 4,150 and 4,550 feet. The soils formed in very deep alluvial deposits of ash and pumice from dacitic pumice flows. The climate is characterized by cold winters with much snow and cool dry summers. The mean annual precipitation is 16 to 30 inches. The mean January temperature is 25 to 27 degrees F.; the mean July temperature is 59 to 62 degrees F.; and the mean annual temperature is 42 to 44 degrees F. The frost-free period is 0 to 50 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chinchallo, Chock, and Lather soils. Chinchallo soils have diatomaceous silt in the upper part of the particle-size control section. Chock soils have ochric epipedons and are ashy. Lather soils are organic soils.
DRAINAGE AND PERMEABILITY: Poorly drained; moderate over rapid permeability. A water table occurs at its upper most limit from March to June. Frequent flooding occurs for brief durations from March to May.
USE AND VEGETATION: Kirk soils are used for irrigated pasture, homesites, and wildlife habitat. Native meadow plants mainly are tufted hairgrass, northern mannagrass, redtop, Nebraska sedge, and Kentucky bluegrass.
DISTRIBUTION AND EXTENT: Lake basins in south-central Oregon near the Cascade Mountains; MLRA 6. The soils are moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Klamath County, Oregon, 1977.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Mollic epipedon - from 0 to 9 inches (A1, A2, and A3 horizons) with an average of 6 percent organic matter.
Andic properties - from 0 to 60 inches (A1, A2, A3, AB, and BC horizons)
Particle-size control section - from 0 to 40 inches and based on the thickest part (upper 25 inches of BC horizon) which meets ashy-pumiceous family criteria. The upper 9 inches meet medial criteria; the zone from 9 to 15 inches meet ashy criteria; and the zone from 15 to 40 inches meet ashy-pumiceous criteria. The pedon and the ranges of 15 bar water (dried) for the medial and ashy parts of the control section do not met the requirements for a medial over ashy contrasting particle-size class when a combination of 15 bar values are associated with the gradual or clear boundary between the A and AB horizon.
Aquic feature - dominant chroma, moist, of 1 or 2 throughout and redox with chroma of 2 beginning at 15 inches.
ADDITIONAL DATA: Characterization data of 2 profiles (S67Oreg. 18-13 and 18-14) reported in Riverside Soil Survey Laboratory report for Kirk soils sampled in Klamath County, Oregon.