LOCATION BUNCHPOINT OR

Established Series
Rev. AEK/DL/RWL
03/2013

BUNCHPOINT SERIES

The Bunchpoint series consists of moderately deep, well drained soils on stable ridge slopes of plateaus. Bunchpoint soils formed in mixed ash, loess and colluvium derived from basalt. Slopes are 0 to 15 percent. The mean annual precipitation is about 25 inches and the mean annual temperature is about 43 degrees F.

TAXONOMIC CLASS: Coarse-loamy, isotic, frigid Vitrandic Haploxerolls

TYPICAL PEDON: Bunchpoint ashy silt loam - Woodland, on a 2 percent planar slope at an elevation of 5300 feet. (Colors are for moist soil unless otherwise noted.)

Oi--0 to 1 inch; discontinuous slightly decomposed leaves and needles.

A--1 to 13 inches; dark brown (10YR 3/3) ashy silt loam, brown (10YR 5/3) dry; weak fine and very fine subangular blocky structure; soft, friable, slightly sticky and nonplastic; common very fine, many fine, and few medium roots; many fine tubular pores; 10 percent gravel; strongly acid (pH 5.5); clear irregular boundary. (5 to 12 inches thick)

AB--13 to 25 inches; brown (10YR 4/3) ashy silt loam, yellowish brown (10YR 5/4) dry; weak medium and fine subangular blocky structure parting to weak very fine subangular blocky; slightly hard, friable, slightly sticky and nonplastic; common fine and few medium and coarse roots; common fine tubular pores; 10 percent gravel; NaF pH 8.5; strongly acid (pH 5.5); clear irregular boundary. (9 to 12 inches thick)

Bw--25 to 33 inches; dark yellowish brown (10YR 4/4) gravelly silt loam, yellowish brown (10YR 5/6) dry; moderate coarse and weak medium and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few fine, medium, and coarse roots; few fine and medium tubular pores; 20 percent gravel and 5 percent cobbles; strongly acid (pH 5.5); abrupt irregular boundary. (6 to 16 inches thick)

2R--33 inches; basalt bedrock

TYPE LOCATION: Wallowa County, Oregon, 960 feet south and 1340 feet west of the northeast corner of Section 22, T.3S., R.47E. (Latitude 45 degrees, 17 minutes, 25 seconds N; Longitude 116 degrees, 55 minutes, 38 seconds W)

RANGE IN CHARACTERISTICS: The soil is dry for 60 to 75 consecutive days during the summer between the depths of 8 and 25 inches. The mean annual soil temperature is 42 to 45 degrees F. Depth to bedrock is 20 to 40 inches. The mollic epipedon is 10 to 20 inches thick. The particle-size control section has 12 to 18 percent clay, more than 15 percent sand coarser than very fine sand and 15 to 35 percent rock fragments. Hue is 10YR or 7.5YR. Soil reaction is slightly acid to strongly acid.

The A horizon has value of 2 or 3 moist, 4 or 5 dry and chroma of 2 or 3 moist or dry. It is ashy silt loam with 5 to 15 percent clay. It has 0 to 10 percent gravel. It has 0.4 to 0.9 percent acid oxalate extractable aluminum plus one-half iron and 5 to 15 percent volcanic glass.

The AB horizon has value of 3 or 4 moist, 5 or 6 dry and chroma of 3 or 4 moist or dry. It is ashy silt loam, ashy loam, or ashy fine sandy loam with 12 to 18 percent clay, 0 to 10 percent gravel, and 0 to 5 percent cobbles. It has 0.4 to 0.8 percent acid oxalate extractable aluminum plus one-half iron and 5 to 15 percent volcanic glass.

The Bw horizon has value of 4 to 6 moist, 4 to 6 dry and chroma of 3 or 4 moist, 5 or 6 dry. It is gravelly silt loam, gravelly loam, or gravelly very fine sandy loam with 15 to 25 percent gravel and 0 to 10 percent cobbles.

COMPETING SERIES: These are the Dinkelman, Kilmerque, Lani, Lostcreek, Republic, and Thrapp soils. Dinkelman soils are 40 to 60 inches deep to a paralithic contact. Kilmerque soils are dry for 45 to 60 consecutive days, and are 20 to 40 inches deep to a paralithic contact. Lani soils are very deep to bedrock. Lostcreek soils are greater than 60 inches to bedrock, are dry for 45 to 60 consecutive days, and are moderately well drained. Republic soils are greater than 60 inches to bedrock and have 15 to 25 percent coarse and very coarse sand in the particle-size control section. Thrapp soils are 35 to 45 inches to a densic contact and redoximorphic features.

The Fren soils have a similar mixed mineralogy. Fren soils are greater than 60 inches to bedrock, have a mollic epipedon 20 to 35 inches thick, and have secondary carbonates at 20 to 35 inches.

GEOGRAPHIC SETTING: Bunchpoint soils are on stable ridge slopes of plateaus and structural benches. Elevations are 4,000 to 5,400 feet. Slopes are 0 to 15 percent. The soils formed in mixed ash, loess and colluvium derived from basalt. The climate is characterized by cold, wet winters and hot, dry summers. The mean annual precipitation is 20 to 30 inches. The mean annual temperature is 41 to 44 degrees F. The frost-free period is 70 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bocker and Parsnip soils. Bocker soils are on plateaus and have bedrock at a depth of 4 to 10 inches. Parsnip soils are on ridge tops of plateaus and have bedrock at a depth of 10 to 20 inches.

DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.

USE AND VEGETATION: These soils are used for watershed, recreation, livestock grazing, wildlife habitat, and limited timber production. The native vegetation is ponderosa pine, common snowberry, wood's rose, Idaho fescue, bluebunch wheatgrass, prairie junegrass, yarrow, and lupine.

DISTRIBUTION AND EXTENT: Northeastern Oregon; MLRA 9. The series is inextensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Wallowa County Area, Oregon 1998.

REMARKS: Diagnostic horizons and other features recognized in this pedon are:

Mollic epipedon - from 1 to 13 inches (A horizon) with base saturation (NH4OAC) of 58 percent.

Cambic horizon - the zone from 13 to 33 inches (AB and Bw horizons).

Vitrandic feature - the zone from 1 to 25 inches (A and AB horizons) having 0.8 percent acid oxalate extractable aluminum plus one-half iron and 22 to 24 percent volcanic glass.

Ultic feature - the zone from 1 to 25 inches (A and AB horizons) having 48 and 52 percent (respectively) base saturation by sum.

Particle-size control section - the zone from 11 to 33 inches (lower 2 inches of A horizon and the AB and Bw horizons)

ADDITIONAL DATA: Partial laboratory data is available for this pedon. Reference sample S92OR-063-010 for Wallowa County, Oregon, NSSL, Lincoln, NE, 1/94.

National Cooperative Soil Survey
U.S.A.