Soil order

Entisol

Soil without diagnostic horizons, or almost: recently deposited material (sand, alluvium) or on which the climate did not have time to act.

What it means for farming

Very variable. The sandy ones (Psamentes) retain little water and blow away; alluvial ones (Fluventes) can be good but they flood; the shallow ones on rock (lithic) are barely useful for grazing.

Entisoles on the maps

Ortent

Entisol on material that is neither sandy nor alluvial: eroded slopes, rock, recent sediments.

Psament

Entisol sandy throughout the profile: dunes, sand sheets.

Fluvent

Entisol formed by layers of alluvium left by a river when it overflows; organic matter rises and falls with each layer.

Acuent

Entisol with excess water: saturated near the surface, with redox depletions.

The definitions are a plain-language summary of the USDA Keys to Soil Taxonomy. The formal definition includes thickness, color and percentage thresholds that are left out here.

Sources