LOCATION MAROSA                  NM

Established Series
Rev. JOC/JAW/KLS
09/2022

MAROSA SERIES

The Marosa series consists of deep, well-drained soils that formed in material weathered from andesite, granite and rhyolite. Marosa soils are on sideslopes of mountains and have slopes of 0 to 80 percent. The mean annual precipitation is about 890 mm and the mean annual air temperature is about 4 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Inceptic Haplocryalfs

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

Oi--0 to 3 cm; forest litter in various stages of decomposition.

A--3 to 11 cm; light brownish gray (10YR 6/2) cobbly sandy loam, brown (10YR 5/3) moist; weak thin platy structure parting to weak fine granular; soft, friable; many very fine and fine, few medium and coarse roots; many very fine and fine pores; 15 percent gravel, 20 percent cobbles; neutral (pH 7.0); clear smooth boundary. (5 to 15 cm thick)

E1--11 to 44 cm; light gray (10YR 7/2) and very pale brown (10YR 8/2) extremely gravelly loamy sand, light brownish gray (10YR 6/2) moist; weak fine granular structure; soft, friable; many very fine and fine, few medium and coarse roots; many very fine and fine pores; 60 percent gravel, 15 percent cobbles; neutral (pH 6.8); gradual wavy boundary. (25 to 35 cm thick)

E2--44 to 90 cm; very pale brown (10YR 7/3) extremely gravelly sandy loam, yellowish brown (10YR 5/4) moist; weak fine granular structure; soft, friable; many very fine and fine, few medium and coarse roots; many very fine and fine pores; 60 percent gravel, 15 percent cobbles; neutral (pH 6.6); gradual wavy boundary. (35 to 50 cm thick)

Bt--90 to 115 cm; light yellowish brown (10YR 6/4) extremely gravelly sandy clay loam, yellowish brown (10YR 5/4) moist; moderate fine and medium subangular blocky structure; hard, firm, slightly plastic; thin patchy clay films on faces of peds and on rock fragments; many very fine and fine, few medium roots; few fine pores; 40 percent gravel, 20 percent cobbles; neutral (pH 6.8); clear wavy boundary. (25 to 40 cm thick)

C--115 to 186 cm; cobbles, gravel and stones with some of horizon above. Rock fragments constitute 95 percent of horizon and consist of 45 percent gravel, 35 percent cobbles and 15 percent stones.

TYPE LOCATION: Taos County, New Mexico; SE1/4 NE1/4 section 15, T.29N., R.14E.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--4 to 8 degrees C
Annual summer soil temperature--7 degrees C
Thickness of solum--100 to 150 cm
Depth to the argillic horizon--60 to 90 cm
Rock fragments--angular pebbles, gravel, cobbles and stones of igneous origin

A horizon
Value--6 through 8 dry, 4 through 6 moist
Chroma--2 through 4
Texture--loamy sand, sandy loam, or loam
Rock fragment content--25 to 60 percent gravel and 10 to 15 percent cobbles

Bt horizon
Hue--7.5YR or 10YR
Value--6 or 7 dry, 4 through 6 moist
Chroma--3 through 6
Texture--sandy clay loam or light clay loam
Rock fragment content--40 to 60 percent gravel and 20 to 40 percent cobbles

C horizon
Rock fragment content--90 to 95 percent pebbles, gravel, cobbles and stones

COMPETING SERIES: These are the Bundo, Diamante, Etoe, Mortenson and Tigeron series. Bundo and Etoe soils have mixed E/B and B/E horizons. Diamante and Mortenson soil have more than 35 percent clay in the family control section and Mortenson soils are montmorillonitic.

GEOGRAPHIC SETTING:
Landform--sides of mountains
Elevations--2750 to 3350 meters
Slopes--0 to 80 percent
Parent material--formed in residuum from rhyolite, andesite, granite and related rocks
Mean annual precipitation--760 to 1000 mm occurring as winter snow and rain and late summer rain
Mean annual air temperature--3 to 7 degrees C
Average summer temperature--7 degrees C

GEOGRAPHICALLY ASSOCIATED SOILS: None listed

DRAINAGE AND PERMEABILITY: Well drained; moderate permeability

USE AND VEGETATION: Marosa soils are used for timber production, wildlife habitat, recreation and watershed. Vegetation is Douglas fir, Engelmann spruce, aspen, and scattered subalpine fir. The understory is kinnickinnick, whortleberry, grasses and forbs.

DISTRIBUTION AND EXTENT: Marosa soils are of moderate extent in northern New Mexico and western Wyoming; MLRAs 43B, 48A, 48B

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Taos Area, New Mexico, 1976

REMARKS: Converted to metric, updated formatting, and O horizons were updated to start at zero. Competing series section was not updated. 7/2022

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National Cooperative Soil Survey
U.S.A.