LOCATION VONDERGREEN OR

Established Series
Rev. RTS/GLG/RWL
06/2011

VONDERGREEN SERIES

The Vondergreen series consists of deep, somewhat poorly drained soils that formed in colluvium and residuum from metasedimentary or metavolcanic rock. Vondergreen soils are in depressional areas and narrow drainageways on broad ridgetops of coastal hills and mountains. Slopes are 0 to 30 percent. The mean annual precipitation is about 110 inches and the mean annual temperature is about 54 degrees F.

TAXONOMIC CLASS: Fine, isotic, isomesic Aquic Hapludults

TYPICAL PEDON: Vondergreen silt loam, woodland, on a 15 percent south-facing slope at an elevation of 500 feet. (Colors are for moist soil unless otherwise noted.)

Oi--0 to 1 inch; slightly decomposed needles, leaves, twigs, and woody materials.

A1--1 to 6 inches; dark brown (7.5YR 3/2) silt loam, dark grayish brown (10YR 4/2) dry; strong very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine, very fine and medium roots; many fine and very fine irregular pores; 2 percent very fine gravel and 5 percent soft rock fragments; very strongly acid (pH 4.8); clear smooth boundary.

A2--6 to 10 inches; brown (7.5YR 4/2) silt loam, dark grayish brown (10YR 4/2) dry; moderate very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine, very fine and medium roots; many very fine and fine continuous tubular pores; 5 percent fine gravel and 5 percent soft rock fragments; very strongly acid (pH 4.8); abrupt smooth boundary. (Combined thickness of the A horizon ranges from 5 to 16 inches)

Bt1--10 to 17 inches; dark yellowish brown (10YR 4/4) silty clay loam, yellowish brown (10YR 5/4) dry; moderate medium subangular blocky structure; hard, firm, sticky and plastic; common fine and very fine roots; many very fine continuous tubular pores; few faint clay films in pores; 5 percent gravel and 10 percent soft rock fragments; very strongly acid (pH 4.6); clear smooth boundary. (5 to 8 inches thick)

Bt2--17 to 25 inches; light olive brown (2.5Y 5/4) silty clay loam, very pale brown (10YR 7/4) dry; moderate medium subangular blocky structure; hard, firm, sticky and plastic; common fine and very fine roots; common very fine continuous tubular pores; common fine prominent grayish brown (2.5Y 5/2) redox depletions and strong brown (7.5YR 4/6) masses of iron accumulation; few distinct clay films on faces of peds and in pores; 10 percent gravel and 15 percent soft rock fragments; very strongly acid (pH 4.6); clear smooth boundary.

Bt3--25 to 39 inches; gray (2.5Y 5/1) silty clay, white (10YR 8/1) and brownish yellow (10YR 6/6) dry; weak coarse subangular blocky structure; very hard, very firm, very sticky and very plastic; few fine roots; few very fine continuous tubular pores; many fine prominent brown (7.5YR 4/4) and strong brown (7.5YR 5/6) masses of iron accumulation; many prominent clay films on faces of peds and in pores; few black (10YR 2/1) manganese stains; 10 percent gravel and 15 percent soft rock fragments; very strongly acid (pH 4.6); gradual smooth boundary.

Bt4--39 to 54 inches; gray (2.5Y 5/1 ) gravelly silty clay; white (10YR 8/1) and brownish yellow (10YR 6/6) dry; weak coarse subangular blocky structure; very hard, very firm, very sticky and very plastic; few fine roots; few very fine continuous tubular pores; many fine prominent brown (7.5YR 4/4) and strong brown (7.5YR 5/6) masses of iron accumulation; many prominent clay films on faces of peds and in pores; few black (10YR 2/1) manganese stains; 30 percent gravel and 20 percent soft rock fragments; very strongly acid (pH 4.6); gradual wavy boundary. (Combined thickness of the Bt1, Bt2, Bt3, and Bt4 horizons ranges from 27 to 40 inches)

Cr--54 inches; weathered shale.

TYPE LOCATION: Curry County, Oregon; located about 2970 feet south and 5200 feet west of the northeast corner of section 18, T. 41 S., R. 12 W., W.M. (Latitude 42 degrees, 00 minutes, 45 seconds N; Longitude 124 degrees, 10 minutes, 18 seconds W)

RANGE IN CHARACTERISTICS: The soils are usually moist and are dry for less than 45 consecutive days between 4 and 12 inches in the four months following the summer solstice. The mean annual soil temperature is 54 to 59 degrees F. The difference between the mean summer and mean winter soil temperature is 5 to 9 degrees F. The particle-size control section averages 35 to 50 percent clay and has 10 to 35 percent rock fragments. Depth to redox depletions with chroma of 2 or less is 12 and 24 inches. The solum is 40 to 60 inches thick and is extremely acid to very strongly acid throughout. Depth to a paralithic contact is 40 to 60 inches.

The A horizon has hue of 10YR or 7.5YR, value of 2 to 4 moist, 4 or 5 dry and chroma of 2 or 3 moist and dry. Moist values of 2 only occur within the upper 8 inches of the A horizon. It is silt loam with 15 to 25 percent clay. It has 0 to 10 percent gravel and 0 to 15 percent soft gravel-size rock fragments.

The Bt1 horizon has hue of 10YR or 7.5YR, value of 4 to 6 moist and dry and chroma of 4 or 5 moist and dry. It is silt loam or silty clay loam with 25 to 35 percent clay. It has 0 to 10 percent gravel and 0 to 15 percent soft gravel-size rock fragments.

The Bt2, Bt3, and Bt4 horizons have hue of 2.5Y moist, 7.5YR or 10YR dry, value of 5 or 6 moist, 6 to 8 dry and chroma of 0 to 4 moist and 1 to 6 dry. It is silty clay loam, silty clay or gravelly silty clay with 35 to 50 percent clay. It has 10 to 30 percent gravel, 0 to 5 percent cobbles, and 0 to 20 percent soft gravel-size rock fragments.

COMPETING SERIES: This is the Shinglemill series. Shinglemill soils are more than 60 inches deep to bedrock, have moist value of 5 or 6 in the surface E horizon extending to a depth of 8 inches, and are poorly drained.

GEOGRAPHIC SETTING: Vondergreen soils are in depressional areas and narrow drainageways on broad ridgetops of coastal hills and mountains. Slopes are 0 to 30 percent. The soils formed in colluvium and residuum derived from metasedimentary or metavolcanic rock of the Dothan Formation. Elevations are 200 to 1,300 feet. The climate is humid, characterized by warm wet winters and warm moist summers with fog. A strong marine influence limits the dirurnal and annual range of temperature. The mean annual precipitation is 90 to 130 inches. The mean annual temperature is 52 to 57 degrees F. The frost-free period is 240 to 300 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bosland, Dulandy, Floras, Guerin, Loeb, Macklyn, Wedderburn, and Zwagg soils. Bosland, Dulandy, Floras, Guerin, Wedderburn, and Zwagg soils lack argillic horizons. Loeb soils are well drained. Macklyn soils are 20 to 40 inches deep to a paralithic contact.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow permeability. A perched high water table fluctuates between depths of 1.0 to 3.0 feet below the surface from November through May.

USE AND VEGETATION: These soils are used mainly for timber production, watershed, recreation, and wildlife habitat. Native vegetation is Douglas-fir, coastal redwood, red alder, bigleaf maple, tanoak, California laurel, cascara buckthorn, evergreen huckleberry, willow, salal, salmonberry, red huckleberry, and western swordfern.

DISTRIBUTION AND EXTENT: Coastal hills and mountains of southwestern Oregon; MLRA 4B. The series is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES ESTABLISHED: Curry County, Oregon, 1995.

REMARKS: Diagnostic horizons and features recognized in this pedson include:

Ochric epipedon - (A1 horizon mollic color extends to a depth of 6 inches).

Argillic horizon - the from 10 to 54 inches. (Bt1, Bt2, Bt3, Bt4 horizons)

Particle-size control section - from 10 to 30 inches (Bt1, Bt2, and upper Bt3 horizons)

Aquic feature - redox depletions with value moist of 4 or more and chroma of 2 or less at a depth of 17 to 25 inches (Bt2 horizon) with associated high chroma redox concentrations.

National Cooperative Soil Survey
U.S.A.