LOCATION MACKLYN OR

Established Series
Rev. MHF/RTS/RWL
05/2015

MACKLYN SERIES

The Macklyn series consists of moderately deep, well drained soils that formed in colluvium and residuum from metasedimentary or metavolcanic rock. Macklyn soils are on broad ridgetops of coastal hills and mountains. Slopes are 0 to 30 percent. The mean annual precipitation is about 2794 millimeters (110 inches) and the mean annual temperature is about 12 degrees C (54 degrees F).

TAXONOMIC CLASS: Fine, isotic, isomesic Typic Haplohumults

TYPICAL PEDON: Macklyn silt loam, woodland, on a 5 percent southwest-facing slope at an elevation of 158 meters (520 feet). (Colors are for moist soil unless otherwise noted.)

Oi -- 0 to 3cm (0 to 1 in); slightly decomposed litter of needles, leaves, twigs, and woody materials.

A1 -- 3 to 18 cm (1 to 7 in); dark reddish brown (5YR 3/2) silt loam, brown (7.5YR 4/4) dry; strong very fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine, very fine and medium roots throughout; many fine irregular pores; very strongly acid (pH 4.8); clear smooth boundary.

A2 -- 18 to 33 cm (7 to 13 in); dark reddish brown (5YR 3/3) silt loam, brown (7.5YR 5/4); strong very fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and few medium roots throughout; many fine irregular pores; 5 percent gravel; very strongly acid (pH 4.8); abrupt wavy boundary. (Combined thickness of the A horizons range from 20 to 38 cm)

Bt1 -- 33 to 58 cm (13 to 23 in); reddish brown (5YR 4/4) silty clay loam, light brown (7.5YR 6/4) dry; moderate medium subangular blocky structure; hard, firm, sticky and plastic; common fine, very fine and few medium roots throughout; many fine and very fine continuous tubular pores; few distinct clay films on ped faces and in pores; 5 percent gravel; very strongly acid (pH 4.6); clear wavy boundary.

Bt2 -- 58 to 76 cm (23 to 30 in); reddish brown (5YR 4/4) silty clay, reddish yellow (5YR 6/6) dry; moderate medium subangular blocky structure; very hard, very firm, very sticky and very plastic; few fine and very fine roots throughout; many fine and very fine continuous tubular pores; many prominent clay films on ped faces and in pores; 30 percent soft rock fragments and 10 percent hard gravel; very strongly acid (pH 4.6); clear wavy boundary.

Bt3 -- 76 to 97 cm (30 to 38 in); reddish brown (5YR 4/4) gravelly clay; reddish yellow (5YR 6/6) dry; weak medium subangular blocky structure; very hard, very firm, very sticky and very plastic; few fine and very fine roots throughout; many fine and very fine continuous tubular pores; many prominent clay films on ped faces and in pores; 40 percent soft rock fragments and 20 percent gravel; very strongly acid (pH 4.6); gradual wavy boundary. (Combined thickness of the Bt horizons range from 30 to 81 cm)

Cr -- 97 cm (38 in); weathered sandstone.

TYPE LOCATION: Curry County, Oregon; located about 3960 feet south and 3960 feet west of the northeast corner of section 18, T. 41 S., R. 12 W., W.M.(Latitude 41 degrees, 59 minutes, 54 seconds N; Longitude 124 degrees, 10 minutes, 02 seconds W)

RANGE IN CHARACTERISTICS:

Soil moisture: The soils are usually moist and are dry less than 45 consecutive days between 10 and 30 cm in the four months following the summer solstice. The soils have an udic soil moisture regime.

Soil temperature: The mean annual soil temperature is 12 to 15 degrees C. The difference between mean summer and mean winter soil temperature varies from 3 to 6 degrees C. The soils have an isomesic soil temperature regime.

Assume low base saturation (less than 35 percent) based on low pH and lab data from geographically associated soils.
The umbric epipedon is 20 to 38 cm thick.
Depth to bedrock is 50 to 100 cm.
The particle-size control section (weighted average):
Clay content: 30 to 45 percent
Rock fragments: 0 to 30 percent

O horizon

Hue: 10YR.
Value: 2 through 6 dry and moist.
Chroma: 1 through 4 dry and moist.
Texture: slightly decomposed organic material.
Wood fragments: 0 to 35 percent.
Reaction: moderately to slightly acid.

A or Ap horizons

Hue: 5YR or 7.5YR
Value: 2 or 3, or 4 or 5 dry
Chroma: 2 or 3, or 3 or 4 dry
Texture of fine earth: silt loam
Clay content: 15 to 25 percent
Rock fragments: 0 to 10 percent gravel; 0 to 15 percent paragravel
Reaction: very strongly acid

Upper Bt horizons

Hue: 5YR or 7.5YR
Value: 4 or 5, or 5 or 6 dry
Chroma: 4 to 6 moist or dry
Texture of fine earth: silty clay loam
Clay content: 27 to 35 percent
Rock fragments: 0 to 15 percent gravel; 0 to 20 percent paragravel
Reaction: very strongly acid

Lower Bt horizons

Hue: 5YR or 7.5YR
Value: 4 or 5, or 4 to 6 dry
Chroma: 4 to 6 moist or dry
Texture of fine earth: silty clay loam, clay, or silty clay
Clay content: 35 to 45 percent
Rock fragments: 5 to 30 percent gravel; 20 to 40 percent paragravel
Reaction: very strongly acid

COMPETING SERIES: These are the Bullgulch, Hunterscove, Loeb, and Winchuck series. Bullgulch and Hunterscove soils have a mean annual soil temperature of less than 12 degrees C. In addition, Bullgulch soils have an umbric epipedon 51 to 76 cm thick, hue of 10YR throughout the Bt horizon, and are greater than 102 cm to bedrock. Loeb soils are 102 to 152 cm deep to a paralithic contact. Winchuck soils have more than 45 percent clay in the control section and are more than 102 cm deep to bedrock.

GEOGRAPHIC SETTING: Macklyn soils are on broad ridgetops of coastal hills and mountains. Slopes are 0 to 30 percent. The soils formed in colluvium and residuum derived dominantly from metasedimentary or metavolcanic rock types of the Dothan Formation. Elevation is 61 to 396 m. The climate is humid, characterized by warm wet winters and warm moist summers with fog. A strong marine influence limits the diurnal and annual range of temperature. The mean annual precipitation is 2286 to 3302 mm. The mean annual temperature is 11 to 14 degrees C. The frost-free period is 240 to 300 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bosland, Dulandy, Floras, Guerin, Vondergreen, Wedderburn, Zwagg and the competing Loeb soils. Bosland, Dulandy, Floras, Guerin, Loeb, Vondergreen, and Wedderburn soils are on adjacent ridgetops and side slopes. Zwagg soils are on adjacent open grassland ridgtops and side slopes. Bosland, Dulandy, Floras, Guerin, Wedderburn and Zwagg soils lack argillic horizons. Vondergreen soils are somewhat poorly drained.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; high to very high runoff; low saturated hydraulic conductivity.

USE AND VEGETATION: The soils are used for timber production, homesites, pasture, watershed, recreation, and wildlife habitat. Native vegetation is Douglas-fir, coastal redwood, tanoak, California laurel, cascara buckthorn, evergreen huckleberry, salal, red elderberry, western swordfern, Pacific rholodendron, cascade Oregon grape, and common beargrass.

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 pedon include:

1. Umbric epipedon - from 3 to 33 cm (A1 and A2 horizons).
2. Argillic horizon - from 33 to 97 cm (Bt1, Bt2, and Bt3 horizons).
3. Particle-size control section - from 33 to 83 cm (Bt1, Bt2, and upper Bt3 horizons).

Humults feature - 17 kg of organic carbon per square meter to a depth of 97 cm and 1.1 to 2.9 percent organic carbon in the Bt1 horizon.

Soil classified using the 11th Edition of the Keys to Soil Taxonomy
NASIS User Pedon ID 95OR015005

National Cooperative Soil Survey
U.S.A.