Science · Soils

Mollisol

Soils with a qualifying dark, base-rich mollic surface, commonly associated with grassland.

USDA Soil Taxonomy order

Profile

Surface: Mollic epipedon under taxonomic criteria
Bases: High base saturation is diagnostic
Subsoil: May contain contrasting textures and restrictive horizons
Fertility: Productive potential does not eliminate testing needs

Water & soil targets

Moisture (VWC): Site-calibrated; measure field capacity and dry-down
Salinity tolerance: Not inferable from soil classification; test EC, sodicity and water chemistry
Drought tolerance: Not inferable from taxonomy; measure accessible storage and plant response

Soil orders and WRB groups are not textures. Determine horizon-specific retention, field capacity, drainage, rooting depth and seasonal hydrology before setting irrigation triggers.

Problems to watch

Topsoil loss
Compaction
Salinity in susceptible settings

Stress signs

Eroded pale patches
Restricted roots
Salt crusts

Where you'll find it

Grassland management
Landscape soil conservation

More soils

Sand Loamy Sand Sandy Loam Loam Silt Loam Clay Loam

All Science profiles

General agronomic guidance and typical ranges; actual targets vary by site, soil, climate and season.