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EC

EC measures how salty the soil water is.

Also called: electrical conductivity, salinity EC, mS/cm, µS/cm

Speed
  1. EC measures how salty the soil water is.
  2. High EC stresses roots; it is not the same as drought.
  3. Read the unit. mS and µS differ by a thousand.
  4. Different soil to water ratios are not comparable.
  5. White crust plus worse wilt after watering often means EC went up.
  6. Don’t spread gypsum on every white crust.

How it appears on the sheet

The sheet says EC or conductivity. The unit — mS or µS — is the whole story.

A sketch. Do not fertilise from the picture alone.

Common units

Often mS/cm or dS/m, sometimes μS/cm. Different soil:water ratios are not the same number.

Soil:water ratio · Saturated paste, 1:1 and 1:5 EC are different numbers.

How to read the number

EC says how salty the soil water is, not that the plant is thirsty. Seedlings feel it first.

White crust plus scorched margins: split salt from potassium. Rates live in the saline guides.

Thresholds only, not a prescription. Rates live in the field guide. This page does not hand you a bag count.

Low / mid / high (sketch)
CellLowMidHigh
Topsoil EC (sketch, often 1:5)Very low is not itself a diseaseMost open fields still come upSeedlings suffer; dripper rings, worse wilt after water

Regional classes differ. This table is a comparison, not a prescription.

What it looks like in the field

White crust, a ring at the dripper, worse wilt after a light watering — EC often went up. Salt is EC; alkali is pH and sodium.

Don’t do this

  • Don’t copy the number across units.
  • Don’t gypsum every white crust.
  • No drain, no flood.

Lesson video