Soil Bulk Density and Compaction
Bulk density, total porosity, and compaction flag against texture-class threshold.
Example
You enter
- Dry core mass (g) 200
- Core volume (cc) 150
- Particle density (g/cc) 2.65
- Texture loam
You get
- Bulk density 1.33 g/cc
- Porosity 0.497
- Compaction threshold 1.8
- Compacted No
Checked against published worked examples from: USDA-NRCS.
Details, formula, and sources
Formula or tableBulk density (g/cm³) = dry_weight / volume. Total porosity = 1 − (bulk_density / particle_density), particle density typical 2.65 g/cm³ for mineral soils.
Source and editionUSDA NRCS Soil Survey Manual (SSM) and Soil Quality Indicators by name.
Free accessUSDA NRCS materials free at nrcs.usda.gov.
What governsEstimate. AHJ and licensed professional govern.
API field namesdry_mass_g, core_volume_cc, particle_density_pcc, texture, bulk_density, total_porosity, compaction_threshold, compacted
- Particle density 2.65 g/cm³ for mineral soils unless user suppliesUSDA NRCS SSM
- Compaction threshold bulk density that restricts root growth, by texture: sand, sandy loam, loam 1.80; silt loam, clay loam 1.75; silty clay loam 1.65; clay 1.47 g/cm³ (root growth already affected at 1.69 sand, 1.63 sandy loam and loam / 1.60 / 1.55 / 1.39)USDA NRCS Soil Quality Indicators