Release of Nitrogen by Burning Light Forest Fuels

Abstract Smokes produced by burning pine litter, green needles, and fuels of lower nitrogen content were drawn through dilute acid solutions which were then nesslerized in the presence and absence of titanous sulfate. Kjeldahl analyses of fuels and residues indicated that 62% of the nitrogen contained in pine litter and leaf materials was released by burning. No ammonia was detected in combustion gases. Only minor amounts (0.3% and less) of the nitrogen released by burning were detected by nesslerization (+TiSO 4 ) of dilute acid solutions. We concluded that only small amounts (0.30 − 0.48 kg/ha ‐1 for typical loblolly stands) of nitrogen released by forest fires could be returned to the soil via precipitation and be made available for tree growth. Most nitrogen in organic matter presumably is volatilized as nitrogen gas.