LOCATION DANDREA            AZ
Established Series
Rev. GEW/JEJ
12/2006

DANDREA SERIES


The Dandrea series consists of moderately deep, well-drained soils that formed in material weathered from schist and related rocks. These soils are on rolling to very steep hills or mountains. The mean annual precipitation is about 21 inches and the mean annual air temperature is about 43 degrees F.

TAXONOMIC CLASS: Fine, smectitic, frigid Typic Argiustolls

TYPICAL PEDON: Dandrea gravelly loam, forested. (Colors are for dry soil unless otherwise noted.)

0i--0 to 1 inch; raw and decomposing pine and oak litter. (1 to 3 inches thick)

A1--1 to 4 inches; dark grayish brown (10YR 4/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; strong fine and medium granular structure; soft, friable, slightly sticky and plastic; many very fine roots; many very fine interstitial pores; noneffervescent; neutral (pH 7.0); clear smooth boundary. (2 to 4 inches thick)

A2--4 to 8 inches; dark grayish brown (10YR 4/2) gravelly loam, very dark brown (10YR 2/2) moist; moderate fine granular structure; soft, friable, sticky and plastic; many very fine and fine and common medium roots; many very fine interstitial pores; noneffervescent; neutral (pH 7.2); clear smooth boundary. (4 to 8 inches thick)

Bt1--8 to 13 inches; reddish yellow (7.5YR 6/6) gravelly clay loam, brown (7.5YR 4/4) moist; weak fine subangular blocky and moderate medium granular structure; slightly hard, friable, sticky and plastic; common very fine and many fine, medium and coarse roots; common very fine interstitial pores; common thin clay films on peds; noneffervescent; neutral (pH 7.0); gradual irregular boundary. (1 to 8 inches thick)

Bt2--13 to 30 inches; brown (7.5YR 5/4) gravelly clay, brown (7.5YR 4/4) moist; common medium faint reddish yellow (7.5YR 7/6) mottles, strong brown (7.5YR 5/6) moist; moderate medium subangular and angular blocky structure; very hard, firm, sticky and very plastic; few very fine and common fine, medium and coarse roots; common very fine interstitial pores; common moderately thick clay films on peds; noneffervescent; neutral (pH 6.8); abrupt irregular boundary. (8 to 20 inches thick)

Cr--30 to 51 inches; brown (7.5YR 5/4) weathered schist, strong brown (7.5YR 5/6) moist; thin tongues of gravelly clay B2t soil material in seams; common fine faint reddish yellow (7.5YR 6/6) mottles, strong brown (7.5YR 5/6) moist; massive and rock controlled structure; very hard, firm, sticky and plastic; few fine, medium and coarse roots; common very fine interstitial pores; common thin clay films on pebbles; noneffervescent; neutral (pH 7.0).

TYPE LOCATION: Yavapai County, Arizona; about .2 mile SE of junction of Groom Creek and Hassayampa Creek; 500 feet south and 800 feet west of SW corner sec. 33, T.13N., R.2W.

RANGE IN CHARACTERISTICS:

Depth to C horizon or weathered schist: 20 to 40 inches

Gravel and cobbles: 15 to 35 percent by volume

Mean annual soil temperature: about 45 degrees F.

Soil moisture: The soil is usually moist in some part of the soil between depths of 10 and 40 inches. Typic ustic moisture regime.

A horizon
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 2 through 4.

Bt horizons
Hue: 7.5YR or 10YR, dominantly 7.5YR
Value: 5 through 7 dry, 3 through 5 moist
Chroma: 4 through 6 dry and moist
Texture: gravelly clay loam and gravelly clay
Clay content: more than 35 percent but less than 60 percent clay
Thin tongues of the Bt horizon extent into the C material to depths of 60 inches or more in some pedons.

COMPETING SERIES: These are the:
Absarokee (MT) - lithic contact between depths of 20 to 40 inches.
Acree (CO) - very deep, hues of 5YR or redder in the argillic horizon; a discontinuity in the argillic horizon.
Barela (NM) - has a lithic contact of basalt at 40 to 60 inches.
Capillo (NM) - deep, paralithic contact at 40 to 60 inches.
Delson (CO) - very deep.
Ekah (MT) - very deep, has a calcic horizon.
Herm (CO) - very deep.
Morapos (CO) - very deep, dry in all parts of the moisture control section for 45 consecutive days after the middle of July.
Moreno (NM) - very deep.
Nortez (CO) - lithic contact between depths of 20 to 40 inches.
Pramiss (CO) - has Btk horizons.
Ricot (CO) - very deep, hues of 5YR or redder in the argillic horizon; a discontinuity in the argillic horizon.
Tamaneen (MT) - over 35 percent coarse fragments between the depths of 20 and 40 inches.
Tukunnik (UT) - deep, lithic contact at 40 to 60 inches.
Work () - very deep.
Zau (CO) - formed in colluvium and residuum derived from shale and sandstone.

GEOGRAPHIC SETTING: Dandrea soils are at elevations of 6,000 to 8,000 feet in a subhumid continental climate. These soils formed in place on weathered schist or closely related materials. Dandrea soils are on rolling to very steep schist hills or mountains with slopes ranging from 15 to 60 percent. The average annual precipitation ranges from 18 to 25 inches and occurs mainly as thunderstorms in July and August and gentle rains or snow during the winter and spring. The mean annual temperature is about 43 degrees F. The frost-free season is 90 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Arp, Mirabal and Moano soils and the Barkerville, Brolliar and Gaddes soils. Barkerville soils are dark-colored, lack and argillic horizon and are in a loamy, mesic family. Brolliar soils have mollic epipedons and formed on basalt. Gaddes soils are moderately fine-textured and have mean annual temperature warmer than 47 degrees F.

DRAINAGE AND PERMEABILITY: Well-drained; medium runoff; slow permeability.

USE AND VEGETATION: Used for timber production, rangeland and recreation. Vegetation is mainly ponderosa pine, Gambel oak and Douglas-fir, with an understory of mutton bluegrass and squirreltail.

DISTRIBUTION AND EXTENT: Yavapai County in north-central Arizona. This series is of moderate extent. MLRAs 35 & 39.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona

SERIES ESTABLISHED: Western Yavapai County Area, Yavapai County, Arizona, 1971.

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

Mollic epipedon - The zone from 1 to 8 inches (A horizons)

Argillic horizon - The zone from 8 to 30 inches (Bt horizons)

Paralithic contact - at 30 inches (Cr horizon)

Classification changed from Mollic Eutroboralfs to Typic Haplustalfs in 2000. Classification changed from Typic Haplustalfs to Typic Argiustolls in 2006.

Classified according to Keys to Soil Taxonomy Tenth Edition, 2006


National Cooperative Soil Survey
U.S.A.