Methods for the detection and quantification of ammonium picrate and picric acid in soil and water were developed. Picrate ions were extracted from water directly or from acetone extracts of soil by solid-phase, acidic, ion-exchange materials. Elution from the ion exchangers was accomplished by converting the retained picrate to picric acid using strong aqueous, acid-organic solvent mixtures. The resulting colorless solution was then converted back to a colored picrate solution by dilution with water. Quantification and correction for background interferences were based on spectrophotometric measurements. A colorimetric, chemical confirmation of picrate was possible for the water method. The method detection limits were determined to be 1.3 mg/g for soil and 3.6 mg/L for water. Both methods can be implemented under field conditions.