LOCATION WYNTOON CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, isotic, mesic Andic Palexeralfs
TYPICAL PEDON: Wyntoon medial sandy loam--on a 2 percent southwest-facing slope under white fir, ponderosa pine, incense-cedar, and Saskatoon serviceberry at about 4,000 feet elevation--forestland. (Colors are for dry soil unless otherwise noted. When described August 27, 1980, the soil was slightly moist below 29 inches) The soil surface has discontinuous patches of fresh and partially decomposed conifer needles, twigs and bark up to 1 inch thick.
A1--0 to 2 inches; brown (10YR 4/3) medial sandy loam, very dark brown (10YR 2/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, common fine and medium roots; common very fine tubular and interstitial pores; 8 percent gravel; sodium fluoride pH is 10.7; moderately acid (pH 6.0); abrupt smooth boundary.
A2--2 to 9 inches; brown (7.5YR 4/4) medial sandy loam, dark brown (7.5YR 3/2) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and medium roots; common very fine tubular and interstitial pores; 9 percent gravel; sodium fluoride pH is 10.4; slightly acid (pH 6.4); clear smooth boundary. (Combined thickness of the A horizons is 6 to 9 inches)
Bt1--9 to 19 inches; brown (7.5YR 4/4) loam, dark reddish brown (5YR 3/4) moist; moderate fine and medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; few very fine, common fine and coarse roots; many very fine, common fine and medium tubular pores; few faint clay films lining pores and common bridges between mineral grains; 8 percent gravel; sodium fluoride pH is 10.3; neutral (pH 6.6); clear smooth boundary.
Bt2--19 to 25 inches; brown (7.5YR 5/4) loam, dark reddish brown (5YR 3/4) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few, very fine, medium and common fine roots; many very fine, common fine and medium tubular pores; many distinct clay films on faces of peds and lining pores; 7 percent gravel; sodium fluoride pH is 10.0; neutral (pH 7.0); clear wavy boundary. (Combined thickness of the Bt1 and Bt2 horizons is 14 to 20 inches.)
2Bt3--25 to 36 inches; light brown (7.5YR 6/4) silty clay loam, reddish brown (5YR 4/4); moderate medium subangular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; few fine and medium roots; many very fine, common fine and few medium pores; many distinct clay films on faces of peds and common prominent clay films lining pores; sodium fluoride pH is 9.8; neutral (pH 7.0); diffuse wavy boundary.
2Bt4--36 to 49 inches; light brown (7.5YR 6/4) clay loam, reddish brown (5YR 4/4) moist; moderate medium subangular blocky structure; hard, friable, moderately sticky and slightly plastic; few fine and medium roots; many very fine and common fine tubular pores; many distinct clay films on faces of peds and lining pores; sodium fluoride pH is 9.8; neutral (pH 7.0); clear smooth boundary.
2Bt5--49 to 58 inches; pink (7.5YR 7/4) clay, strong brown (7.5YR5/6) moist; moderate medium subangular blocky structure; very hard, friable, moderately sticky and moderately plastic; few fine roots; many very fine tubular pores; common distinct clay films on faces of peds and lining pores; sodium fluoride pH is 9.8; neutral (pH 7.0); clear wavy boundary.
2Bt6--58 to 67 inches; reddish yellow (7.5YR 7/6) clay, strong brown (7.5YR 5/6) moist; moderate medium subangular blocky structure; very hard, firm, moderately sticky and moderately plastic; few fine roots; common very fine tubular pores; common distinct clay films on faces of peds and lining pores; 10 percent gravel 2 to 75 mm in diameter; sodium fluoride pH is 9.9; neutral (pH 7.0); clear wavy boundary.
2Bt7--67 to 74 inches; reddish yellow (7.5YR 8/6) clay, strong brown (7.5YR 5/6); moderate medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few fine roots; common very fine tubular pores; few faint clay films lining pores; sodium fluoride pH is 9.8; neutral (pH 7.0). (Combined thickness of the 2Bt horizons is more than 40 inches)
TYPE LOCATION: Siskiyou County, California; about 0.2 mile north of the McCloud River Railroad tracks; approximately 1,240 feet east and 1,400 feet south of the northwest corner of section 34, T. 40 N., R. 1 E.; USGS Bartle 7.5 minute topographic quadrangle; 41 degrees 16 minutes 25 seconds north latitude and 121 degrees 50 minutes 43 seconds west longitude, NAD27.
RANGE IN CHARACTERISTICS:
Soil moisture - The soil moisture control section (7 to 19 inches) is dry in all parts from early July to mid October (100 to 110 days) and is moist in all parts from early December to mid April; The soil temperature exceeds 41 degrees F. from early April to early December (245 days) and exceeds 47 degrees F. from early May to mid December; Xeric moisture regime.
Mean annual soil temperature - 47 to 52 degrees F.
Ochric epipedon thickness - 6 to 9 inches.
Depth to base of argillic horizon - More than 60 inches.
Particle-size control section - Clay content: Averages 20 to 27 percent; Rock fragments: 0 to 15 percent, mainly gravel. Lithology of fragments are volcanic rocks such as andesite, basalt, and rhyolite.
Other features - Rock fragments on the soil surface are mainly gravel or cobbles and range from 0 to 5 percent.
A horizons - Dry color: 10YR 4/3 4/4 5/4; 7.5YR 4/4, 5/4, 5/6 6/4, 6/6; 5YR 5/4, 4/4 or 6/4.
Moist color: 10YR 2/2, 3/2; 7.5YR 3/2, 3/4, 4/4; 5YR 3/3, 3/2, or 3/4 Those colors that are dark, lack the thickness to qualify for an umbric epipedon.
Clay content: 10 to 15 percent.
Organic carbon content: 1.5 to 4.5 percent.
Sodium fluoride pH: 10 to 11.
Reaction: Moderately acid through neutral.
Base saturation: 40 to 50 percent by ammonium acetate and 30 to 35 percent by sum of cations.
Moist bulk density: 0.95 to 1.0 g/cm3.
Other features: These horizons have andic soil properties and medial textural modifiers.
Bt horizons - Dry color: 10YR 6/8; 7.5YR 4/4, 5/4, 5/6, or 5YR 4/6.
Moist color: 7.5YR 3/4, 4/4, or 4/6; 5YR 3/4, 4/4, or 4/6.
Clay content: 20 to 25 percent.
Organic carbon content: 0.6 to 1.0 percent.
Sodium fluoride pH: 9.5 to 10.5.
Reaction: Moderately acid through neutral.
Base saturation: 55 to 70 percent by ammonium acetate and 40 to 50 percent by sum of cations.
Moist bulk density: 1.1 to 1.3 g/cm3.
2Bt horizons - Dry color: 7.5YR 6/4, 7/4, 7/6, or 8/6.
Moist color: 7.5YR 4/4, 4/6, or 5/6; 5YR 4/4, 4/6, or 5/6; Dry and moist chroma of 6 always occurs within a depth of 60 inches.
Texture: Clay loam, silty clay loam, or clay.
Clay content: 35 to 50 percent.
Organic matter content: 0.3 to 0.5 percent.
Sodium fluoride pH: 9.5 to 10.0.
Reaction: Moderately acid through neutral.
Base saturation: 60 to 75 percent by ammonium acetate and 50 to 60 percent by sum of cations.
COMPETING SERIES: There are currently no other series in this family.
GEOGRAPHIC SETTING: Wyntoon soils are on hills and fan remnants. These soils formed in volcanic ash and alluvium derived from volcanic rocks. Slopes are 2 to 30 percent. Elevations range from 3,200 to 4,300 feet. The climate is subhumid with cold, moist winters and warm, dry summers. The mean annual precipitation is 40 to 50 inches including annual snowfall of 60 to 84 inches. The mean annual temperature is 46 to 50 degrees F. The mean January temperature is about 35 degrees F. The mean July temperature is about 65 degrees F. The frost-free period is 80 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Neer, Nikal, Ponto, and Shasta soils. Neer soils are medial-skeletal, moderately deep to paralithic contacts, and occur near lava flow ridges. Nikal soils are medial, moderately deep to lithic contacts, and occur are on the edges of lava flow ridges. Ponto soils are medial and do not have argillic horizons. Shasta soils are ashy, do not have argillic horizons, are occur on outwash plains and alluvial fans.
DRAINAGE AND PERMEABILITY: Well drained; low or medium surface runoff; slow permeability.
USE AND VEGETATION: Wyntoon soils are used for timber production and homesite development. The vegetation is a forest canopy of Jeffrey pine, ponderosa pine, white fir, and incense-cedar with an understory of squawcarpet, Saskatoon serviceberry, deerbrush, tanoak, and whitethorn ceanothus.
DISTRIBUTION AND EXTENT: Northeastern California. These soils are moderately extensive. MLRAs 21 and 22B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Siskiyou County (Intermountain Area Soil Survey), California, 1994.
REMARKS: This revision updates the MLRAs. A revision in March 2004 corrected the type location section. A revision in August 2000 updated the mineralogy class from mixed to isotic and added the medial compositional textural modifier to the two A horizons having andic soil properties.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 9 inches (A1 and A2 horizons).
Andic soil properties - The zone from the soil surface to 9 inches (A1 and A2 horizons).
Argillic horizon - The zone from 9 to more than 60 inches (Bt1, Bt2, 2Bt3, 2Bt4, 2Bt5, 2Bt6, and 2Bt7 horizons).
Particle-size control section - The zone from 9 to 29 inches (Bt1 and Bt2 horizons and part of the 2Bt3 horizon).
ADDITIONAL DATA: The typical pedon at the series type location has full characterization by the Soil Survey Laboratory (SSL), Lincoln, NE, as soil survey sample number S81CA-093-004 (pedon # 81P0714). It was also analyzed by the soils laboratory at UC Davis as # 81-47-153, #1513.
Andic property data from UC Davis lab:
Depth P-ret B.D. NaF Glass Alo Feo 15-bar H20
(in) (%) (g/cm3) (pH) (%) (%) (%) (%)
0-2 95 0.53 10.7 20 3.05 0.49 24.2
2-9 94 0.93 10.4 8 2.12 0.44 21.5
9-19 88 1.04 10.3 4 1.34 0.37 21.9
19-25 73 1.10 10.0 ND 0.75 0.31 23.2
25-36 56 1.12 9.8 1 0.42 0.29 33.0
36-49 56 1.10 9.8 ND 0.45 0.36 37.1
49-58 53 1.10 9.8 ND 0.42 0.40 41.2
58-67 49 1.08 9.9 1 0.39 0.40 43.4
67-74 53 1.02 9.8 ND 0.50 0.48 45.0