Spectrum Technologies Field Scout 2266FS Product Manual page 23

Interpreting EC Readings from Soilless Media
The FieldScout EC meter allows for quick and easy
readings of salinity in a greenhouse container. The
following equations give an approximation of how a
direct-insert reading relates to more conventional soil
sampling techniques. The FieldScout reading is
designated by the variable FS.
Pour-through Method (PT)
PT = 1.637 * FS + 0.556
1:2 Dilution (OTT)
OTT = 0.448 * FS - 0.13
Saturated Media Extract (SME)
SME = 1.178 * FS - 0.294
Source:
Scoggins, H. L., VanIersal, M.W. 2006. In Situ
Probes for Measurement of Electrical Conductivity of
Soilless Substrates: Effects of Temperature and
Substrate Moisture Content. HortScience. 41:210-
214
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