PROCEDURE

1. Dry soil for 12 hours at 80 °C
2. Weigh 2.00 g soil into a tared porcelain crucible.
3. Place into a furnace for 4 hours at 550 °C.
4. Cool in a desiccator and weigh.
5. Prepare one duplicate sample and one quality control sample with each set of samples analyzed.

CALCULATION

% ORGANIC MATTER = ( Loss in weight ÷ 2.00 ) × 100

QUALITY CONTROL

1. Values on the duplicate samples must agree within 20% of the average value for the two samples.
2. Values on the quality control sample must lie within the established limits for this sample.

NOTE

This method should be used if the soil organic matter is greater than 6.7%

REFERENCE

1. Cuniff, P. A. (ed). Official Methods of Analysis of AOAC International, 16th edition. Method 2.7.08. Chapter 2. p 37.