Soil series profile

Aloha soil series

Aloha is a somewhat poorly drained soil with a silt loam surface, mapped on 58,210 acres in 5 counties in OR. Hydrologic group C/D.

#5329 by mapped area fine-silty Aquic Xerochrepts (Inceptisols)

Drainage class: Somewhat poorly drained
Hydrologic group: C/D
Typical topsoil pH: 5.8
Mapped area: 58k

Typical Aloha 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 Aloha horizons (representative values)
Depth	Texture	pH	Clay	Sand	Organic matter
0–8 in (H1)	Silt loam	5.8	18%	14%	2.5%
8–46 in (H2)	Silt loam	6.1	23%	10%	1.25%
46–65 in (H3)	Silt loam	6.1	18%	14%	0.25%

Representative values from the most extensive Aloha map unit (Aloha silt loam, survey area OR067). 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 Aloha soil means for gardens, lawns and septic systems

For gardens

Typical topsoil in Aloha soils is moderately acidic: pH 5.8. 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 >99% of mapped Aloha acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is silt loam (>99% of mapped Aloha acres).

100% of mapped Aloha acres is somewhat poorly to very poorly drained, so soil stays soggy for long spells after rain and in wet seasons. Raised beds, plants that tolerate wet feet, and not working the soil while wet all help.

For lawns and yards

On 100% 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 100% of the acres in mapped Aloha soils very limited, 0% somewhat limited and 0% not limited.

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 Aloha soil is found

Mapped acres

Aloha is mapped in Oregon.

Counties with the most mapped Aloha soil
County	Acres	Share of county land
Washington County, OR	25,194	6.3%
Clackamas County, OR	24,291	4.4%
Yamhill County, OR	4,455	1.0%
Columbia County, OR	2,611	0.7%
Multnomah County, OR	1,658	0.6%

Septic absorption fields

NRCS rating, share of Aloha acres

Not limited 0%

Somewhat limited 0%

Very limited 100%

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

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Septic tank absorption field rating across mapped Aloha acres.
Category	Share of acres
Not limited	0.0%
Somewhat limited	0.0%
Very limited	100.0%

Drainage, water table and flooding

Share of Aloha acres

Depth to seasonal high water table: About 1.7 feet (20 in) (median where reported); within 18 inches on 8% of acres.
Flooding: Not mapped as flooding on most acres.
Slope: Typically 2–4% (median 2%).
Topsoil organic matter: Median 2.5%.

Drainage class

Excessively drained 0%

Somewhat excessively drained 0%

Well drained 0%

Moderately well drained 0%

Somewhat poorly drained 100%

Poorly drained 0%

Very poorly drained 0%

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

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Drainage class across mapped Aloha acres.
Category	Share of acres
Excessively drained	0.0%
Somewhat excessively drained	0.0%
Well drained	0.0%
Moderately well drained	0.0%
Somewhat poorly drained	100.0%
Poorly drained	0.0%
Very poorly drained	0.0%

Hydrologic soil group

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

B: moderate infiltration 0%

C: slow infiltration <1%

D: very slow infiltration (clayey, shallow or wet) 0%

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 >99%

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

Show as a table

Hydrologic soil group across mapped Aloha acres.
Category	Share of acres
A: fast infiltration (mostly sandy or gravelly)	0.0%
B: moderate infiltration	0.0%
C: slow infiltration	0.4%
D: very slow infiltration (clayey, shallow or wet)	0.0%
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	99.6%

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 Aloha (component kind "Series") in SSURGO: 58,210 acres.
Method: Shares are by mapped acres of Aloha components. The profile comes from the single largest Aloha component. Full methodology.

Independent reference site. No government affiliation or endorsement.

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