LOCATION HYANNIS COEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Lamellic Haplocryalfs
TYPICAL PEDON: Hyannis gravelly loamy sand - forest. (Colors are for dry soil unless otherwise noted.)
Oi--2 to 1 inch; undecomposed organic material principally needles, bark, twigs, and leaves.
Oe--1 inch to 0; partially decomposed organic material like that of the horizon above.
A--0 to 3 inches; 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 pebbles; moderately acid (pH 5.6); abrupt smooth boundary. (0 to 4 inches thick).
E--3 to 12 inches; 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 pebbles and cobbles; moderately acid (pH 5.6); gradual wavy boundary. (4 to 23 inches thick)
Bt--12 to 30 inches; 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 pebbles; moderately acid (pH 5.6); gradual wavy boundary. (10 to 50 inches thick)
Cr--30 to 50 inches; soft, noncalcareous sandstone with lenses of partially cemented cobbles.
TYPE LOCATION: Jackson County, Colorado; approximately 180 feet north and 1,230 feet 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 is about 40 degrees F. and mean summer soil temperature is about 51 degrees F. Base saturation ranges from 60 to 100 percent in all subhorizons of the argillic horizon. Depth to the paralithic contact ranges from 20 to 40 inches. Rock fragments range from 35 to 75 percent in a major part of the solum and any C horizon and are mainly 1/4 to 10 inches in diameter. These soils are dry in some part of the moisture control section for some period in nearly every year.
The A horizon, if present, has hue of 5Y through 7.5YR, value of 4 or 5 dry, 2 or 3 moist, and chroma of 1 through 3. It ranges from strongly acid to neutral.
The E horizon has hue of 5Y through 7.5YR, value of 5 through 8 dry, 4 through 7 moist, and chroma of 1 through 4. It ranges from moderately acid to neutral.
The Bt horizon has hue of 5Y through 7.5YR and mixed colors ranging in value from 5 through 8 dry, 4 through 7 moist, and chroma of 1 through 6. It ranges from moderately acid to neutral. It is cobbly, very cobbly or very channery with a matrix of loamy sand, loamy fine sand, or sand in which there are discontinuous lamella of sandy loam, loam, and sandy clay loam. This horizon ranges from moderately acid to neutral.
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 40 inches. Yochum soils have sandy loam matrix material and have hue of 5YR or redder.
GEOGRAPHIC SETTING: Hyannis soils are on hills, ridges, and mountainsides. Slopes typically range from about 2 to 60 percent. The soil formed in cobbly or gravelly coarse textured materials weathered from soft sandstone and conglomerate. At the type location the mean annual precipitation is 20 to 25 inches with peak periods of precipitation in the spring and summer. Mean annual temperature is 36 degrees F. and mean summer temperature is 52 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Perceton soils. Perceton soils have a fine-loamy control section.
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: Mountainous areas of Colorado. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Lakewood, Colorado
SERIES ESTABLISHED: Jackson County, Colorado, 1973.
REMARKS: Diagnostic horizons and features recognized in this pedon are: Ochric epipedon from 0 to 3 inches (A horizon)
Albic horizon from 3 to 12 inches (E horizon)
Argillic horizon from 112 to 30 inches (Bt horizon)
Last updated by the state 7/89.