LOCATION GAPPMAYER UTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Alfic Argixerolls
Typifying Pedon: Gappmayer cobbly loam - rangeland
(Colors are for air dry soil unless otherwise noted.)
O1--2 to 0 inches; oak leaves, twigs, and other plant leaves.
A11--0 to 6 inches; very dark grayish brown (10YR 3/2) cobbly light loam, very dark brown (10YR 2/2) moist; weak very fine granular structure; soft, very friable, nonsticky, slightly plastic; common fine and few medium roots; common fine discontinuous pores; neutral (pH 6.7); clear smooth boundary. (2 to 10 inches thick)
A12--6 to 10 inches; brown (10YR 4/3) cobbly light loam, dark brown (10YR 3/3) moist; weak very fine granular structure; soft, very friable, nonsticky, slightly plastic; many fine and few medium roots; many fine discontinuous pores; slightly acid (pH 6.5); clear wavy boundary. (3 to 6 inches thick)
A21--lO to l9 inches; pale brown (10YR 6/3) very cobbly light loam, brown (10YR 5/3) moist; weak thin platy structure; soft, friable, nonsticky, slightly plastic; common fine and few medium roots; common fine discontinuous pores; slightly acid (pH 6.5); clear wavy boundary. (6 to 9 inches thick)
A22--19 to 30 inches; very pale brown (10YR 7/4) very cobbly loam, light yellowish brown (10YR 6/4) moist; weak very fine subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; common fine and few medium roots; common fine discontinuous pores; few thin clay films on faces of peds and in pores; slightly acid (pH 6.4); gradual wavy boundary. (O to 11 inches thick)
B1--30 to 44 inches; light yellowish brown (10YR 6/4) very cobbly loam, yellowish brown (10YR 5/4) moist; weak fine subangular blocky structure; hard, friable, slightly sticky, nonplastic; common fine and few medium roots; common fine discontinuous pores; common thin clay films on faces of peds and in pores; slightly acid (pH 6 .4); gradual wavy boundary. (5 to 14 inches thick)
B2t--44 to 56 inches; light yellowish brown (10YR 6/4) very cobbly loam, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; common fine and few medium roots; common thin clay films on faces of peds and in pores; neutral (pH 6.5); clear smooth boundary. (9 to
16 inches thick)
B3--56 to 63 inches; yellowish brown (10YR 5/4) very cobbly light loam, brown (10YR 4/3) moist; massive; slightly hard, friable, slightly sticky, slightly plastic; common fine and very fine roots; common fine discontinuous pores; few thin clay films mainly in pores; neutral (pH 7.1); clear smooth boundary. ( 7 to 9 inches thick)
Clca--63 to 72 inches; pale brown (10YR 6/3) very cobbly light loam, brown (10YR 4/3) moist; massive; slightly hard, friable, slightly sticky, slightly plastic; few very fine roots; few very fine discontinuous pores; moderately calcareous; lime disseminated and in threads; mildly alkaline (pH 7. 7) .
TYPE LOCATION: Utah County, Utah; about 1 mile south of the Dream Mine on the old Leader Mine Road; 2,000 feet south and 1,000 feet east of the NE corner of sec. 17, T.9S., R.3E.
RANGE IN CHARACTERISTICS: The solum is 30 to 50 inches thick to the bottom of the B2t horizons. The mollic epipedon is less than 20 inches thick. Organic matter decreases regularly or reaches levels of less than 0.5 percent within 50 inches. The soils are usually moist, but are dry in the moisture control section for more than 60 consecutive days during the summers. The mean annual soil temperature is less than 47 degrees F., average summer temperature is 60 to 65 degrees F. The soils are medium acid to neutral. The Al horizon has value of 3 through 5 dry, 1 through 3 moist, and chroma of 2 or 3. The A2 horizon has hue of 10YR through 5YR, value of 4 through 7 dry, 3 through 6 moist and chroma of 2 through 4. It is cobbly sandy loam to very cobbly light loam with 40 to 60 percent coarse fragments, typically cobbles. The Bl horizon has hue of 10YR or 7.5YR, value of 5 or 6 dry, 3 through 5 moist, and chroma of 2 through 4. It is absent in some pedons. The B2t horizon has hue of 10YR through 5YR, value of 5 or 6 dry, 3 through 5 moist, and chroma of 3 through 6. It ranges from very cobbly sandy clay loam to very cobbly loam with more than 18 to 27 percent clay, and with 50 to 80 percent coarse fragments, mainly cobbles. The B3 horizon has value of 5 or 6 dry, 4 or 5 moist, and chroma of 3 or 4. It is very cobbly light loam to very cobbly loamy fine sand, with 50 to 80 percent cobbles.
COMPETING SERIES: These are the McPhie and Norway Flat series. McPhie soils have less than 35 percent coarse fragments in their Bt horizons. Norway Flat soils have less than 18 percent clay in the B2t horizon, and have summer temperature of less than 59 degrees F.
GEOGRAPHIC SETTING: Gappmayer soils are at elevations of 5,500 to 7,200 feet on sloping to very steep northerly facing mountain slopes with gradients of 5 to 70 percent. These soils formed in alluvium and colluvium derived from mixed sedimentary rocks, mainly sandstone and shale. The climate is moist subhumid, having a mean annual temperature of less than 47 degrees F., average summer temperature of 60 to 65 degrees F., and average annual precipitation of 18 to 25 inches. The frost-free period is about 80 to 90 days.
PRINCIPAL ASSOCIATED SOILS: These are the Bezzant, Broadhead, Bradshaw, Henefer, and Wallsburg soils. Bezzant soils lack an argillic horizon. Broadhead and Henefer soils have more than 35 percent clay in the argillic horizon, lack A2 horizons, and have less than 35 percent coarse fragments in the profile. Bradshaw soils have weak B2 horizons and lack A2 horizons. Wallsburg soils are fine textured and have a lithic contact within 20 inches.
DRAINAGE AND PERMEABILITY: Well-drained; medium runoff; moderate to moderately rapid permeability.
USE AND VEGETATION: Rangeland. Native vegetation is big sagebrush, oakbrush, maple, chokecherry, snowberry, and scattered conifer with associated grasses and forbs.
Distribution and Extent: Central and northern Utah. These soils are inextensive.
Series Established: Sanpete Area Utah, 1971.
Remarks: These soils were formerly classified as Gray-Wooded soils intergrading to Brunizems.
OSED scanned by NSSQA. Last revised by state on 8/71.