Tóth, B., T. Tóth, T. Herman, and G. Tóth. 2006. Evaluating methods of in-field soil organic matter analysis. Communications in Soil Science and Plant Analysis. 37 :(No.15-20) The actual content of the soil organic carbon (SOC) have to be periodically measured for soil classification and nutrient management purposes. Traditional SOC tests are relatively time consuming and costly. A rapid field test would be valuable to delineate soil map units with similar SOC, to simplify the process of land evaluation while increasing precision. The objectives of this study are to develop and evaluate a new field measurement technique for the quick assessment of SOC. The new method measures the emitted CO2 concentration three minutes after treatment of soil sample with acidic potassium permanganate solution. The inorganic carbonate content of the soil is measured separately with the addition of sulphuric acid only. Carbon-dioxide concentration from both procedures is measured with a portable infrared gas analyzer. The difference between the concentrations measured after the two separate reactions provide an estimate of SOC. Samples from brown forest soils (ca Hapludalf) (0.19-5.53 % SOC) were used for the method development. The correlation coefficient between the SOC determined by the new method and laboratory wet combustion method content was 0.76 for the full range of SOC, and it was 0.81 for the soil samples having less than 20% carbonate.