Soil series profile

Chamise soil series

Chamise is a well drained soil with a shaly loam surface, mapped on 99,101 acres in 6 counties in CA. Hydrologic group C.

#3544 by mapped area clayey-skeletal Ultic Palexerolls (Mollisols)

Drainage class: Well drained
Hydrologic group: C
Typical topsoil pH: 5.8
Mapped area: 99k

Typical Chamise profile

Texture and pH by depth

Depth to scale. More strongly shaded layers hold more clay. Horizon names are the soil survey's (A = topsoil, B = subsoil, C = parent material).

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Typical Chamise horizons (representative values)
Depth	Texture	pH	Clay	Sand	Organic matter
0–18 in (H1)	Shaly loam	5.8	23%	40%	4.5%
18–24 in (H2)	Shaly clay	5.3	48%	23%	0.25%
24–37 in (H3)	Very shaly clay	5.3	45%	26%	0.25%
37–60 in (H4)	Very shaly clay loam	5.3	31%	35%	0%

Representative values from the most extensive Chamise map unit (Chamise shaly loam, 15 to 45 percent slopes, survey area CA672). Other map units of this series vary within the series range.

Stock photo for illustration, not a sample of this soil series. Credit on the Sources & method page.

What this means

What Chamise soil means for gardens, lawns and septic systems

For gardens

Typical topsoil in Chamise soils is moderately acidic: pH 5.8 (most land between 5.8 and 6.2). Many vegetables grow well here, and some gardens benefit from a little lime. Test before adding any.

Loamy topsoil (loam, silt loam and similar) covers 71% of mapped Chamise acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is shaly loam (39% of mapped Chamise acres).

72% of mapped Chamise acres is moderately well to excessively drained, which suits most garden plants.

For lawns and yards

On 71% of mapped acres, rain soaks in slowly (hydrologic groups C and D, including dual groups that are D until drained). Expect runoff and puddles after heavy rain: core-aerate compacted lawns and keep ground sloping away from foundations.

For a septic system

For conventional septic absorption fields, NRCS rates 71% of the acres in mapped Chamise soils very limited, 0% somewhat limited and 0% not limited (29% not rated, such as urban land, pits or water).

Where the soil is very limited (slow permeability, a high water table, flooding, shallow bedrock or steep slopes), alternative systems such as mound or sand-filter designs are common and cost more.

Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.

Generated from the mapped numbers above using fixed rules, not a site visit. See how these notes are written.

Where Chamise soil is found

Mapped acres

Chamise is mapped in California.

Counties with the most mapped Chamise soil
County	Acres	Share of county land
Santa Barbara County, CA	50,667	4.5%
Monterey County, CA	43,561	2.0%
San Luis Obispo County, CA	4,648	0.3%
Contra Costa County, CA	142	0.0%
San Benito County, CA	1	0.0%
Alameda County, CA	0	0.0%

Septic absorption fields

NRCS rating, share of Chamise acres

Not limited 0%

Somewhat limited 0%

Very limited 71%

Not rated 29%

Septic tank absorption field rating across mapped Chamise acres. Scale 0 to 100% of mapped land.

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Septic tank absorption field rating across mapped Chamise acres.
Category	Share of acres
Not limited	0.0%
Somewhat limited	0.0%
Very limited	71.4%
Not rated	28.6%

Drainage, water table and flooding

Share of Chamise acres

Depth to seasonal high water table: None reported within about 6.5 feet (median where reported).
Flooding: Not mapped as flooding on most acres.
Slope: Typically 12–53% (median 30%).
Topsoil organic matter: Median 4.5%.

Drainage class

Excessively drained 0%

Somewhat excessively drained 0%

Well drained 72%

Moderately well drained 0%

Somewhat poorly drained 0%

Poorly drained 0%

Very poorly drained 0%

Not rated 28%

Drainage class across mapped Chamise acres. Scale 0 to 100% of mapped land.

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Drainage class across mapped Chamise acres.
Category	Share of acres
Excessively drained	0.0%
Somewhat excessively drained	0.0%
Well drained	72.3%
Moderately well drained	0.0%
Somewhat poorly drained	0.0%
Poorly drained	0.0%
Very poorly drained	0.0%
Not rated	27.7%

Hydrologic soil group

A: fast infiltration (mostly sandy or gravelly) 0%

B: moderate infiltration 0%

C: slow infiltration 71%

D: very slow infiltration (clayey, shallow or wet) <1%

A/D: D as is, A if drained 0%

B/D: D as is, B if drained 0%

C/D: D as is, C if drained 0%

Not rated 29%

Hydrologic soil group across mapped Chamise acres. Scale 0 to 100% of mapped land.

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Hydrologic soil group across mapped Chamise acres.
Category	Share of acres
A: fast infiltration (mostly sandy or gravelly)	0.0%
B: moderate infiltration	0.0%
C: slow infiltration	70.5%
D: very slow infiltration (clayey, shallow or wet)	0.9%
A/D: D as is, A if drained	0.0%
B/D: D as is, B if drained	0.0%
C/D: D as is, C if drained	0.0%
Not rated	28.6%

Sources & data dates

Source: USDA NRCS Soil Survey Geographic Database (SSURGO), queried through Soil Data Access. Public domain.
Data date: SSURGO as published on November 3, 2026 (most recent survey area update October 26, 2026). NRCS refreshes SSURGO each October.
Scope: All map unit components named Chamise (component kind "Series") in SSURGO: 99,101 acres.
Method: Shares are by mapped acres of Chamise components. The profile comes from the single largest Chamise component. Full methodology.

Independent reference site. No government affiliation or endorsement.

Full narrative description: USDA Official Soil Series Description for Chamise.