Laboratory Analysis

Soil Fertility (continued)

Soil Science Basics

Soil & the Environment

Working with soil

Soil & Students

Soil & Agriculture

Preparation and Extraction

1. Fill the extraction tube from your Soil Test Kit to the 30 mL line with distilled water.

water in tube

2. Add 2 Floc-Ex tablets. Cap the tube and mix well until both tablets have disintegrated.

Shake tube

3. Remove the cap and add one heaping spoonful of dry, sieved soil.

Adding soil to tube

4. Cap the tube and shake for one minute.

Shaking tube

5. Let the tube stand until the soil settles out (usually about 5 minutes). The clear solution above the soil will be used for the nitrate (N), phosphorus (P), and potassium (K) tests.

Settled mixture

Note: For some soils, especially those with a high clay content, there may not be enough clear solution extracted. If more clear solution is needed, repeat steps 1-5.

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Last Updated: September 13, 2001