Aptos series

The Aptos series consists of moderately deep, well drained soils on mountains and hills. These soils formed in material weathered from sandstone, siltstone, or shale. Slope ranges from 15 to 75 percent. Mean annual precipitation ranges from 25 to 60 inches, and mean annual air temperature ranges from 55 to 59 degrees F.

Aptos soils are similar to Felton, Lompico, and Nisene soils. They are mapped in a complex with Nisene soils and are near Ben Lomond, Catelli, Felton, Lompico, and Sur soils. Felton and Nisene soils have a paralithic contact at a depth of more than 40 inches. Lompico soils have a mollie epipedon less than 20 inches thick. Ben Lomond, Catelli, and Sur soils do not have a B2t horizon and average less than 18 percent clay in the control section.

Typical pedon of Aptos fine sandy loam in an area of Nisene-Aptos complex, 50 to 75 percent slopes, about 0.1 mile north-northwest of Woodland Way on Love Creek Road and about 350 feet uphill east of Love Creek Road in SE1/4NW1/4, sec. 33, T. 9 S., R. 2 W. (projected):

0-1 inch to 0; twigs and leaves from plant cover; slightly acid; abrupt smooth boundary.

A11-0 to 9 inches; dark grayish brown (10yR 4/2) fine sandy loam, dark brown (7.5YR 3/2) moist; moderate coarse angular blocky structure; slightly hard, friable, nonsticky and nonplastic; many medium roots and common fine and very fine roots; many medium pores, common fine and very fine tubular pores, and common very fine interstitial pores; slightly acid; clear wavy boundary.

A12-9 to 18 inches; brown (7.5YR 5/2) fine sandy loam, dark brown (7.5YR 3/2) moist; weak coarse angular blocky structure; slightly hard, friable, nonsticky and nonplastic; many medium and coarse roots and common fine and very fine roots; many very fine and fine tubular pores and common very fine interstitial pores; few worm casts; slightly acid; clear wavy boundary.

A13-18 to 23 inches; grayish brown (10YR 5/2) fine sandy loam, dark brown (7.5YR 3/2) moist; weak coarse angular blocky structure; hard, friable, slightly sticky and slightly plastic; many medium and coarse roots and common fine and very fine roots; common fine and very fine tubular pores and many very fine interstitial pores; medium acid; clear wavy boundary.

B2t-23 to 29 inches; brown (10YR 5/3) clay loam, dark brown (7.5YR 3/2) moist; moderate medium and coarse angular blocky structure; hard, friable, sticky and plastic; many medium and coarse roots and common fine and very fine roots; many very fine pores, common fine tubular pores and few very fine interstitial pores; common thin clay films lining pores and coating faces of peds; very strongly acid; gradual irregular boundary.

Cr-29 to 39 inches; weathered fine-grained sandstone, can be dug with moderate difficulty; very strongly acid.

The depth to paralithic contact ranges from 20 to 40 inches. The mollic epipedon is 20 to 40 inches thick. The profile is 0 to 25 percent pebbles.

The A horizon has hue of 10YR or 7.5YR, value of 3 to 5, and chroma of 1 to 3. It is fine sandy loam or loam. It ranges from medium acid to neutral.

The B2t horizon commonly has hue of 10YR, value of 4 or 5, and chroma of I to 4. In places, at a depth of more than 20 inches, it has hue of 10YR, value of 6, and chroma of 3. The B2t horizon is loam, sandy clay loam, or clay loam. It ranges from very strongly acid to slightly acid.

The C horizon, where present, is as much as 15 inches thick. The Cr horizon is sandstone, siltstone, or weathered shale.