LOCATION HYANNIS                 CO

Established Series
Rev. AJC-LF-KLS
03/2023

HYANNIS SERIES

The Hyannis series consists of moderately deep, well drained soils on hills, ridges, and mountainsides. They formed in cobbly or gravelly materials weathered from soft sandstone and conglomerate. Slopes are 2 to 60 percent. The mean annual precipitation is about 510 mm, and the mean annual air temperature is about 2 degrees C.

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

TYPICAL PEDON: Hyannis gravelly loamy sand - forest. (Colors are for dry soil unless otherwise noted.)

Oi--0 to 3 cm; undecomposed organic material principally needles, bark, twigs, and leaves.

Oe--3 to 6 cm; partially decomposed organic material like that of the horizon above.

A--6 to 14 cm; brown (10YR 5/3) fine sandy loam, dark brown (10YR 3/3) moist; strong fine crumb and granular structure; soft, very friable, nonsticky, nonplastic; 10 percent gravel; moderately acid (pH 5.6); abrupt smooth boundary. (0 to 10 cm thick).

E--14 to 37 cm; very pale brown (10YR 8/3) gravelly loamy sand, pale brown (10YR 6/3) moist weak very thick platy structure; soft, very friable; 15 percent gravel and cobbles; moderately acid (pH 5.6); gradual wavy boundary. (10 to 58 cm thick)

Bt--37 to 83 cm; mixed yellowish brown (10YR 5/4) and very pale brown (10YR 7/4) very cobbly loamy sand containing lamellae and seams of sandy clay loam, dark yellowish brown (10YR 4/4) and light yellowish brown (10YR 6/4) moist; weak medium subangular blocky structure; slightly hard, very friable; some of the more clayey peds are hard, friable, slightly sticky, slightly plastic; thin clay films on the more clayey peds and in root channels and pores; thin clay films are on the underside of some rock fragments; 65 percent cobbles and some gravel; moderately acid (pH 5.6); gradual wavy boundary. (25 to 125 cm thick)

Cr--83 to 134 cm; soft, noncalcareous sandstone with lenses of partially cemented cobbles.

TYPE LOCATION: Jackson County, Colorado; about 55 meters north and 375 meters east of SW corner, Sec. 15, T. 5 N., R. 78 W. Longitude 106 degrees, 07 minutes, 58 seconds W.; latitude 40 degrees, 23 minutes, 6 seconds N.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--4 degrees C
Mean summer soil temperature--11 degrees C
Soil moisture--These soils are dry in some part of the moisture control section for some period in nearly every year.
Depth to paralithic contact--50 to 100 cm

Particle-size control section:
Base saturation--60 to 100 percent
Rock fragment content--35 to 75 percent in a major part of the solum and any C horizon and are mainly 5 to 250 mm in diameter.

A horizon, if present
Hue--5Y through 7.5YR
Value--4 or 5 dry, 2 or 3 moist
Chroma--1 through 3
Reaction--pH 5.1 to 7.3

E horizon
Hue--5Y through 7.5YR
Value--5 through 8 dry, 4 through 7 moist
Chroma--1 through 4
Reaction--pH 5.6 to 7.3

Bt horizon
Hue--5Y through 7.5YR
Value--5 through 8 dry, 4 through 7 moist
Chroma--1 through 6
Texture--loamy sand, loamy fine sand, or sand, with discontinuous lamella of sandy loam, loam, and sandy clay loam
Rock fragment content--35 to 75 percent gravel, cobbles and/or channers
Reaction--pH 5.6 to 7.3

COMPETING SERIES: These are the Origo (NM), Siebert (CO), Troutville (CO), and Yochum (CO) series. Siebert soils have a high proportion of mica in the fine earth fraction. Origo and Troutville soils lack a paralithic contact within a depth of 100 cm. Yochum soils have sandy loam matrix material and have hue of 5YR or redder.

GEOGRAPHIC SETTING:
Landform--hills, ridges, and mountainsides
Elevation--2500 to 2800 meters
Slope--2 to 60 percent
Parent material--cobbly or gravelly coarse textured materials weathered from soft sandstone and conglomerate
Mean annual precipitation--510 to 640 mm, with peak periods of precipitation in the spring and summer
Mean annual air temperature--2 degrees C
Mean summer air temperature--11 degrees C
Frost-free period--20 to 30 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed.

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

USE AND VEGETATION: These soils are used for grazing land and timber production. Native vegetation is lodgepole pine, spruce, fir, juniper, and elk sedge. In the understory, grouse whortleberry is common.

DISTRIBUTION AND EXTENT: Hyannis soils are of small extent in the mountains of Colorado; MLRA 48A.

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

SERIES ESTABLISHED: Jackson County, Colorado, 1973

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon--6 to 14 cm (A horizon)
Albic horizon--14 to 37 cm (E horizon)
Argillic horizon--37 to 83 cm (Bt horizon)

Converted to metric and O horizons were updated to start at zero. Competing series section was not updated. 01/2023

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National Cooperative Soil Survey
U.S.A.