LOCATION PUZZLEBARK              OR

Established Series
Rev. JRG-JVC-JBF
05/2011

PUZZLEBARK SERIES

The Puzzlebark series consists of shallow to a duripan, well drained soils that formed in volcanic ash and slope alluvium derived from tuff and tuff-breccia. Puzzlebark soils are on structural benches. Slopes are 0 to 5 percent. The mean annual precipitation is about 250 mm and the mean annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Ashy, glassy, frigid, shallow Vitrixerandic Haplodurids

TYPICAL PEDON: Puzzlebark gravelly ashy fine sandy loam--on a 2 percent slope at an elevation of 1,367 meters--forest land. (Colors are for dry soil unless otherwise noted.) The soil surface has a discontinuous layer of undecomposed pine needles.

A--0 to 5 cm; grayish brown (10YR 5/2) gravelly ashy fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine, many fine, and few medium roots; many fine interstitial pores; 15 percent gravel; slightly alkaline (pH 7.6); abrupt smooth boundary. (5 to 10 cm thick)

Bw--5 to 20 cm; light brownish gray (10YR 6/2) ashy sandy loam, dark grayish brown (10YR 4/2) moist; weak and moderate fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine, common fine, and common medium roots; many fine tubular pores; 10 percent gravel; slightly alkaline (pH 7.6); clear smooth boundary. (15 to 30 cm thick)

Bqk--20 to 36 cm; light gray (10YR 7/2) gravelly ashy sandy clay loam, yellowish brown (10YR 5/4) moist; moderate fine and medium subangular blocky structure; moderately hard, firm, slightly sticky and slightly plastic; few coarse, few fine, and common medium roots; common fine tubular pores; 20 percent gravel; coarse and very coarse sand grains are mainly pumiceous ash; few fine coats of secondary silica on faces of peds; secondary carbonates segregated as few fine coats on bottom of rock fragments; slightly effervescent; slightly alkaline (pH 7.8); clear smooth boundary. (0 to 18 cm thick)

Bqkm1--36 to 43 cm; very pale brown (10YR 8/2) cemented material, light yellowish brown (10YR 6/4) moist; strong medium and thick platy structure; rigid; very strongly cemented by secondary silica; very few fine and very few medium roots between plates; secondary carbonates segregated as few fine coats on faces of peds; violently effervescent; moderately alkaline (pH 8.0); clear wavy boundary. (3 to 8 cm thick)

Bqkm2--43 to 53 cm; very pale brown (10YR 7/3) cemented material, light yellowish brown (10YR 6/4) moist; moderate and strong medium and thick platy structure; rigid; very strongly cemented by secondary silica; very few fine and very few medium roots between plates; secondary carbonates segregated as few fine coats on faces of peds; violently effervescent; moderately alkaline (pH 8.0); abrupt wavy boundary. (10 to 20 cm thick)

2R--53 cm; basaltic tuff; few coats of opal on upper surface of bedrock.

TYPE LOCATION: Lake County, Oregon; in the Lost Forest Research Natural Area northeast of Christmas Lake Valley; approximately 450 feet east and 1,200 feet north of the southwest corner of section 27, T. 25 S., R. 20 E.; USGS Sand Rock 7.5 minute topographic quadrangle; latitude 43 degrees 22 minutes 22 seconds N and longitude 120 degrees 18 minutes 54seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in winter and spring, dry from mid-June to mid-October; aridic moisture regime that borders on xeric.
Mean annual soil temperature: 7 to 8 degrees C.
Depth to base of cambic horizon: 20 to 40 cm.
Depth to thin duripan: 28 to 41 cm.
Depth to bedrock: 40 to 60 cm to a lithic contact.
Volcanic glass content: 40 to 60 percent in coarse silt through fine sand fractions in the A horizon; 60 to 80 percent in the Bw and Bqk horizons.

Particle-size control section - Clay content: 10 to 18 percent.
Rock fragments: 0 to 25 percent, mainly gravel. Lithology of fragments are volcanic rocks such as basalt, tuff, and tuff-breccia.

A horizon
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Structure: Weak fine granular or weak very thin and thin platy parting to weak fine granular.

Bw horizon
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 2 or 3 dry, 2 through 4 moist.
Texture: Ashy sandy loam or gravelly ashy sandy loam.
Clay content: 10 to 20 percent.
Rock fragments: 0 to 20 percent.
Consistence: Slightly hard or hard dry, very friable to firm moist.
Effervescence: Noneffervescent or slightly effervescent.


Bqk horizon
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 2 or 3 dry, 2 through 4 moist.
Texture: Gravelly ashy sandy clay loam, ashy sandy clay loam, gravelly ashy sandy loam, or ashy sandy loam.
Clay content: 10 to 25 percent.
Rock fragments: 0 to 25 percent.
Reaction: Slightly alkaline or moderately alkaline.
Calcium carbonate equivalent: 1 to 5 percent.

Bqkm horizons
Value: 7 or 8 dry, 5 or 6 moist.
Chroma: 2 or 3 dry, 3 or 4 moist.
Consistence: Rigid or very rigid.
Cementation: Very strongly cemented or indurated.
Effervescence: Strongly effervescent or violently effervescent.

COMPETING SERIES: There are currently no other series in this family.

GEOGRAPHIC SETTING: Puzzlebark soils are on structural benches. They formed in volcanic ash and slope alluvium derived from basaltic tuff and tuff-breccia. Slopes are 0 to 5 percent. Elevations range from 1,345 to 1,485 meters. The climate is semiarid with cold, moist winters and warm, dry summers. The mean annual precipitation is 200 to 280 mm, with an annual snowfall of about 530 mm. The mean annual temperature is 6 to 7degrees C. The frost-free period is 50 to 80 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Lostforest, Morehouse, and Sandrock soils. Lostforest soils are ashy, moderately deep to lithic contacts, and have cambic horizons. Morehouse soils are ashy, very deep, do not have diagnostic subsurface horizons, and occur on adjacent dunes. Sandrock soils are ashy, shallow to lithic contacts, and have argillic horizons.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; very high surface runoff; high saturated hydraulic conductivity.

USE AND VEGETATION: Puzzlebark soils are used for livestock grazing, wildlife habitat, and recreation. Prior to designation as a Research Natural Area by the Bureau of Land Management, ponderosa pine was commercially harvested in the Lost Forest. The present vegetation is a forest canopy of ponderosa pine and western juniper with an understory of antelope bitterbrush, mountain big sagebrush, Idaho fescue, Thurber's needlegrass, and Sandberg's bluegrass.

DISTRIBUTION AND EXTENT: South-central Oregon. These soils are not extensive with about 600 acres of the series mapped to date. MLRA 23.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.

SERIES ESTABLISHED: Lake County (Northern Part), Oregon, 2006. The named is coined from the bark of ponderosa pine.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 18 cm (A horizon and part of the Bw horizon).
Cambic horizon - The zone from 5 to 36 cm (Bw and Bqk horizons).
Duripan - The zone from 36 to 53 cm (Bqkm1 and Bqkm2 horizons).
Lithic contact - The boundary at 53 cm to underlying hard bedrock (2R layer).
Particle-size control section and ashy substitute class with glassy mineralogy - The zone from the soil surface to 36 cm (A, Bw, and Bqk horizons).

ADDITIONAL DATA: Volcanic glass percentages determined locally by optical grain count using a polarizing petrographic microscope. Temperature and precipitation means based on climate data observed at Silver Lake Ranger Station (43 degrees, 7 minutes N, 121 degrees, 4 minutes W; 1,335 meters elevation) between 1953 and 1999.

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National Cooperative Soil Survey
U.S.A.