LOCATION MCGARVEY CAEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, isomesic Ultic Hapludalfs
TYPICAL PEDON: McGarvey loam - in Huddart County Park on an east-facing slope of 52 percent and 1,800 feet in elevation. (Colors are for dry soil unless otherwise stated. When described April 14, 1981, the soil was moist throughout.)
0i--4 to 3 inches; undecomposed tanoak and redwood leaves and twigs.
0e--3 to 0 inches; decomposed tanoak and redwood leaves and twigs.
A1--0 to 3 inches; pinkish gray (7.5YR 6/2) loam, dark brown (7.5YR 3/2) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many coarse and few very fine, fine, and medium roots; many very fine and fine tubular and iterstitial, and common medium tubular pores; 10 percent 2 to 5 mm angular pebbles; slightly acid (pH 6.5); clear smooth boundary. (1 to 3 inches thick)
A2--3 to 7 inches; light brown (7.5YR 6/4) loam, brown (7.5YR 4/2) moist; moderate fine and medium subangular blocky structure; very hard, friable, slightly sticky and slightly plastic; many very fine, fine, medium, and coarse roots; many very fine and fine tubular and interstitial, and common medium tubular pores; 6 percent 2 to 5 mm angular pebbles; slightly acid (pH 6.5); gradual wavy boundary. (2 to 4 inches thick)
Bt1--7 to 14 inches; light reddish brown (5YR 6/4) clay loam, yellowish red (5YR 4/6) moist; moderate medium and coarse subangular blocky structure; extremely hard, firm, slightly sticky and slightly plastic, common coarse and many fine and medium roots; common fine and medium tubular and interstitial pores; 2 percent 2 to 5 mm angular pebbles; common thin clay films on peds, in pores and as bridges; neutral (pH 7.0); gradual wavy boundary. (4 to 9 inches thick)
Bt2--14 to 27 inches; light reddish brown (5YR 6/4) clay loam, brown (7.5YR 5/4) moist; moderate medium and coarse subangular blocky structure; extremely hard, firm, sticky and plastic; many coarse and common fine and medium roots; common fine and medium tubular and interstitial pores; 3 percent 2 to 5 mm angular pebbles; common thin clay films on ped faces, in pores, and as bridges; neutral (pH 7.0); gradual wavy boundary. (8 to 14 inches thick)
Bt3--27 to 37 inches; variegated light reddish brown (5YR 6/3) and reddish brown (5YR 5/4) clay, reddish brown (5YR 4/4) moist; moderate medium and coarse subangular blocky structure; extremely hard, firm, sticky and plastic; many coarse and few fine and medium roots; common very fine and fine tubular and interstitial pores; 3 percent 2 to 5 mm angular pebbles; common thin clay films on ped faces; slightly acid (pH 6.2); clear wavy boundary. (5 to 10 inches thick)
Cr--37 to 50 inches; soft fractured sandstone with silty clay loam textures between the rocks.
TYPE LOCATION: San Mateo County, California; in Huddart County Park; 2,750 feet north and 700 feet east of intersection of Skyline Boulevard (Highway 35) and Kings Mountain Road.
RANGE IN CHARACTERISTICS: Depth to a paralithic contact is 20 to 40 inches. The mean annual soil temperature is about 55 degrees F and is usually not below 47 degrees F at any time. The difference between mean winter and mean summer soil temperature is less than 9 degrees F. The soil moisture control section is not dry in any part for as long as 90 cumulative days. Base saturation ranges from 35 to 60 percent. Gravel content ranges from 0 to 10 percent throughout the profile.
The A horizons are 7.5YR 6/2, 6/3, 6/4 dry and 7.5YR 3/2, 4/2 and 4/3 moist. Clay content is 15 to 25 percent.
The Bt horizons are 5YR 5/4, 6/3, 6/4 dry and 5YR 4/4, 4/6; 7.5YR 4/6 and 5/4 moist. Textures are clay loam and clay and the clay content ranges from 27 to 45 percent.
COMPETING SERIES: There are no other soils in this family. Soils in other families include the Irmulco (T) and Tramway (T) series. These soils have a fine-loamy textural control section.
GEOGRAPHIC SETTING: McGarvey soils are on mountainous uplands. Slopes are 30 to 75 percent. The soils formed in material weathered from soft sandstone. Elevation is 400 to 2,000 feet. The climate is subhumid with warm, dry summers and cool, moist winter. Summer fog is common. The average annual precipitation is 30 to 40 inches. Average January temperture is 48 degrees F, average July temperature is 60 degrees F, and the mean annual temperature is 54 to 56 degrees F. The frost-free season is 275 to 330 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Alambique (T), Barnabe, Bret (T), and Buriburi (T) soils. The Alambique and Buriburi soils lack an argillic horizon. The Barnabe and Bret soils lack an argillic horizon and are 10 to 20 inches to a lithic contact.
DRAINAGE AND PERMEABILITY: Well drained, rapid to very rapid runoff, slow permeability.
USE AND VEGETATION: Used mainly for wildlife habitat, watershed, recreation, some urban development and timber production. Vegetation is mostly redwoods, Douglas-fir and tanoak.
DISTRIBUTION AND EXTENT: Northern Santa Cruz Range. This series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: San Mateo County, California 1984. Source of name is from McGarvey Creek, San Mateo County, California.
REMARKS: The classification was updated in February 2001 using the Eighth Edition to Soil Taxonomy. This series was formerly classified as fine, mixed, isomesic Ultic Tropudalfs. Competing series were not checked at that time.