Soil Compaction Assessment Calculator

Interpret penetrometer readings at multiple depths to identify compaction layers, estimate rooting depth, and assess yield impact.

Inputs

Cone index at 6" (PSI)

Cone index at 12" (PSI)

Cone index at 18" (PSI)

Cone index at 24" (PSI)

Soil texture class

Tab to move between fields

Results

Peak compaction (PSI)

300

Compaction depth (in)12

Est. bulk density (g/cm³)1.42

Effective root depth (in)24

Est. yield impact (%)0%

Compaction score (0-100)54

DiagnosisSlight compaction present — monitor and maintain cover crops

How to Use This Calculator

Enter penetrometer readings in PSI at 0-6 inch, 6-12 inch, and 12-18 inch depths.
Input soil moisture percentage at the time of testing.
Set the crop type to apply the compaction threshold relevant to root development.
Review the Compaction Layer Depth and the Tillage Recommendation.
Use the Root Penetration Restriction output to decide whether deep tillage or cover crops are warranted.

How the result changes with Cone index at 12" (PSI)

Cone index at 12" (PSI)	Peak compaction (PSI)
100	250
350	350
650	650
900	900

What each input means

Cone index at 6" (PSI): Penetrometer reading at 6 inches depth in PSI.
Cone index at 12" (PSI): Penetrometer reading at 12 inches depth in PSI.
Cone index at 18" (PSI): Penetrometer reading at 18 inches depth in PSI.
Cone index at 24" (PSI): Penetrometer reading at 24 inches depth in PSI.
Soil texture class: 1=Sandy, 2=Loam, 3=Clay. Affects root-limiting threshold and bulk density estimate.

What each result means

Peak compaction (PSI): Highest cone index value found across all sampled depths.
Compaction depth (in): Depth at which maximum compaction was measured.
Est. bulk density (g/cm³): Estimated bulk density at the most compacted layer.
Effective root depth (in): Deepest root penetration before hitting root-limiting compaction.
Est. yield impact (%): Approximate crop yield reduction from restricted rooting depth.
Compaction score (0-100): Overall score — 100 = no compaction, 0 = severe throughout.

How this is calculated

Worked example, using the default values

Identify Input Parameters
4 parameters
Cone index at 6 = 180, Cone index at 12 = 300, Cone index at 18 = 250, Cone index at 24 = 200 = 5 input(s) provided
Calculate Peak compaction
300 = 300
Calculate Compaction depth
12 = 12
Calculate Est. bulk density
1.42 = 1.42

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Soil Science