LOCATION YAPOAH OR
Established Series
Rev. WMF/TDT
06/2011
YAPOAH SERIES
The Yapoah series consists of very deep, somewhat excessively drained soils on volcanic uplands. They formed in ash and colluvium. Slopes are 0 to 75 percent. The mean annual precipitation is about 25 inches and the mean annual temperature is about 44 degrees F.
TAXONOMIC CLASS: Ashy-skeletal, glassy, frigid Humic Vitrixerands
TYPICAL PEDON: Yapoah very cobbly ashy loamy sand - woodland, on a 15 percent northeast-facing slope at 4400 feet elevation. (When described (8/11/86), the soil was dry throughout. Colors are for moist soil unless otherwise noted.)
Oi--0 to 2 inches; slightly decomposed leaves and twigs of ponderosa pine and white fir.
A--2 to 14 inches; dark brown (10YR 3/3) very cobbly ashy loamy sand, brown (10YR 5/3) dry; weak fine granular structure; loose, nonsticky and nonplastic; many very fine and fine and common medium and few coarse roots; many very fine interstitial pores; 10 percent subangular gravel and 30 percent subangular cobbles; 40 percent sand-size pumiceous ash (0.5-2.0 millimeters.); neutral (pH 7.0); gradual wavy boundary. (10 to 16 inches thick)
Bw--14 to 35 inches; dark yellowish brown (10YR 3/4) extremely flaggy ashy loamy sand, yellowish brown (10YR 5/4) dry; single grain; loose, nonsticky and nonplastic; few fine, medium, and coarse roots; many very fine interstitial pores; 10 percent subangular gravel, 50 percent flagstones and 10 percent stones; 40 percent sand-size pumiceous ash (0.5-2.0 millimeters.); neutral (pH 7.0); gradual wavy boundary.
BC--35 to 62 inches; dark yellowish brown (10YR 3/4) extremely flaggy ashy loamy sand, light yellowish brown (10YR 6/4) dry; single grain; loose, nonsticky and nonplastic; few fine, medium and coarse roots; many very fine interstitial pores; 10 percent subangular gravel, 50 percent flagstones and 10 percent stones; 30 percent sand-size pumiceous ash (0.5-2.0 millimeters.); neutral (pH 7.0).
TYPE LOCATION: Deschutes County, Oregon; 500 feet south and 100 feet west of the northeast corner of the northwest quarter of section 9, T. 17 S, R. 10 E. (Latitude 44 degrees, 6 minutes, 48 seconds N, Longitude 121 degrees, 32 minutes, 00 seconds W)
RANGE IN CHARACTERISTICS: These soils are usually moist but are dry in all parts the soil moisture control section for 60 to 90 consecutive days after the summer solstice. The mean annual soil temperature is 40 to 47 degrees F. Depth to bedrock is over 60 inches. Reaction is neutral throughout. The soil contains 60 to 80 percent glass and glass-coated aggregate. Phosphate retention is 40 to 70 percent. The acid oxalate extractable aluminum plus one-half the acid oxalate iron is 0.40 to 1.0 percent. The 15-bar water content on dried and undried samples is 2 to 10 percent. Field estimated clay content is 2 to 10 percent. The mollic epipedon is 10 to 16 inches thick.
The A horizon has hue of 10YR or 7.5YR, value of 2 or 3 moist and 4 or 5 dry and chroma of 2 or 3 moist and 3 or 4 dry. It contains 10 to 20 percent gravel and 25 to 35 percent cobbles. Total rock fragment content ranges from 15 to 55 percent. It contains 25 to 40 percent sand-size pumiceous ash (0.5-2.0 millimeters.).
The Bw and BC horizon has value of 3 to 5 moist and 5 to 7 dry and chroma of 2 through 6 moist and dry. It is very cobbly, extremely cobbly, very flaggy, extremely flaggy, very gravelly ashy loamy sand or ashy sandy loam. It contains 10 to 20 percent gravel, 10 to 50 percent cobbles and 0 to 40 percent stones. Total rock fragment content is 40 to 85 percent. It contains 30 to 60 percent sand-size pumiceous ash (0.5-2.0 millimeters.).
COMPETING SERIES: These are the
Fryrear, McCumber (T),
Pipp,
Silentcone, and
Timberbutte series. Fryrear soils are 20 to 40 inches deep to bedrock. McCumber soils have an umbric epipedon and are not influenced by coarse and very coarse sand-size pumiceous ash. Pipp soils are dry for 45 to 60 consecutive days after the summer solstice, are moderately to strongly acid, and have estimated clay content of 10 to 18 percent. Silentcone soils are moderately deep to a lithic contact. Timberbutte soils have a mollic epipedon 20 to 30 inches thick, have a cambic horizon, and do not have texture of ashy loamy sand in the particle-size control section.
GEOGRAPHIC SETTING: The Yapoah soils are on volcanic uplands at elevations of 3200 to 5700 feet. Slopes are 0 to 75 percent. These soils formed in ash and colluvium. The climate is characterized by cold, wet winters and hot, dry summers. The mean annual precipitation is 14 to 30 inches. The mean annual temperature is 40 to 47 degrees F. The frost-free period is 50 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Shroyton and
Sisters soils. Shroyton soils are on volcanic uplands and are cryic. Sisters soils are on volcanic uplands and are ashy over loamy.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; moderately rapid to rapid permeability.
USE AND VEGETATION: The soils are used for timber production, wildlife habitat, and recreation. Potential vegetation is ponderosa pine, antelope bitterbrush, greenleaf manzanita, and Idaho fescue.
DISTRIBUTION AND EXTENT: Footslopes and plateaus of the eastern slopes of the Cascade Mountains of central Oregon; MLRA 6. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Deschutes County (Upper Deschutes River Area), Oregon, 1992.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
mollic epipedon - from 2 to 14 inches (A horizon)
andic soil properties - Based on the laboratory data from the Wanoga Series. Ash material is from Mt. Mazama.
All depths to diagnostic horizon and other features are measured from the top of the first mineral horizon.
National Cooperative Soil Survey
U.S.A.