Vapors of 11 dinitroaniline herbicides from soil were trapped in a Florisil column under controlled laboratory conditions for a 3-hr period. No vapor losses of nitralin [4-(methylsulfonyl)-2,6-dinitro-N,N-dipropylaniline] and oryzalin (3,5-dinitro-N
4-dipropylsulfanilamide) were detected at the highest temperature, 50 C, from moist Lakeland sand with an air flow of 50 ml/min; whereas, under the same conditions vapor losses approached 25% for benefin (N-butyl-N-ethyl-α,α,α-trifluoro-2,6-dinitro-p-toluidine), profluralin [N-(cyclopropylmethyl)-α,α,α-trifluoro-2,6-dinitro-N-propyl-p-toluidine] and trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine). Vapor losses for the remaining herbicides studied were moderate with values ranging between 2 and 13%. Volatility of all herbicides increased with increasing temperatures of 30, 40, and 50 C. Vapor losses for each herbicide from Hagerstown clay loam, Littleton silt loam and Lakeland sand were statistically different for five of the 11 herbicides.