Islands of Yap, Federated States of Micronesia

Survey Area FM934• Federated States of Micronesia

The dominant drainage class is Well drained and the dominant hydrologic group is D (very slow infiltration, high runoff). The most common soil order is Oxisols — highly weathered tropical soils, deep but nutrient-poor. This report summarizes the major soil map units across the survey area to help you understand what to expect when buying, building, or gardening in Islands of Yap, Federated States of Micronesia. Search your address to find the exact soil composition, drainage, and series details at your specific location.

Soil Map Unit	Acres	Drainage	Hydro Group	Dwellings	Septic
Rumung-Weloy complex, 12 to 30 percent slopes	5K	Well drained	D	Very limited	Very limited
Ilachetomel peat, 0 to 1 percent slopes, frequently flooded	3K	Very poorly drained	A/D	Very limited	Very limited
Rumung-Weloy complex, 30 to 50 percent slopes	3K	Well drained	D	Very limited	Very limited
Yap silty clay loam, 2 to 6 percent slopes	2K	Well drained	A	Not limited	Very limited
Weloy-Rumung complex, 2 to 12 percent slopes	1K	Well drained	C	Somewhat limited	Very limited
Gitam very gravelly silty clay loam, 2 to 6 percent slopes	1K	Somewhat poorly drained	C/D	Very limited	Very limited
Gitam very gravelly silty clay loam, 6 to 12 percent slopes	1K	Somewhat poorly drained	C/D	Very limited	Very limited
Dechel mucky silt loam, 0 to 2 percent slopes, frequently flooded	992	Very poorly drained	C/D	Very limited	Very limited
Rumung-Weloy complex, 50 to 75 percent slopes	967	Well drained	D	Very limited	Very limited
Gagil silty clay loam, 2 to 6 percent slopes	962	Well drained	A	Not limited	Very limited
Yap silty clay loam, 12 to 30 percent slopes	779	Well drained	A	Very limited	Very limited
Yap silty clay loam, 6 to 12 percent slopes	674	Well drained	A	Somewhat limited	Very limited
Gagil silty clay loam, 12 to 30 percent slopes	671	Well drained	A	Very limited	Very limited
Ngedebus sand, 0 to 4 percent slopes, occasionally flooded	557	Somewhat excessively drained	A	Very limited	Very limited
Yap silty clay loam, 0 to 2 percent slopes	502	Well drained	A	Not limited	Very limited
Sonahnpil variant extremely gravelly silt loam, 0 to 4 percent slopes, occasionally flooded	455	Somewhat poorly drained	C	Very limited	Very limited
Gagil silty clay loam, 6 to 12 percent slopes	447	Well drained	A	Somewhat limited	Very limited
Dublon taxadjunct sandy clay loam, 0 to 4 percent slopes, occasionally flooded	385	Somewhat poorly drained	C/D	Very limited	Very limited
Gagil extremely gravelly loam, 2 to 12 percent slopes	360	Well drained	A	Not limited	Very limited
Gagil silty clay loam, 30 to 50 percent slopes	265	Well drained	A	Very limited	Very limited

Soil Orders in This Area

The USDA classifies every soil into one of 12 soil orders. Here are the dominant orders found in this survey area.

Oxisols

Deeply weathered tropical soils. Nutrient-poor despite appearing lush. Rare in the continental US.

Entisols

Young soils with little development — found on floodplains, dunes, and steep slopes. Properties vary widely by setting.

Alfisols

Moderately weathered forest soils with clay-enriched subsoil. Productive for agriculture, generally good for building and septic.

Mollisols

Fertile grassland soils with thick, dark topsoil. Among the best for agriculture, building, and gardening.

Histosols

Organic peat and muck soils formed in wetlands. Very poor for building (compressible) and septic. Often in regulated wetlands.

Inceptisols

Young but developing soils found in mountains and river terraces. Variable properties — check drainage and bedrock depth.

What This Means

Building & Foundations

About 74% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.

Septic Systems

About 100% of soils are rated "very limited" for septic absorption fields. Despite good drainage overall, limitations may stem from shallow bedrock, steep slopes, or seasonal conditions. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.

Gardening & Agriculture

Well-drained soils on sloped terrain — good for most plants but watch for erosion. Terracing, contour planting, and mulching help retain moisture and topsoil. Drip irrigation is more effective than sprinklers on slopes.