Engel, R., Jones, C. and Wallander, R. 2013. Ammonia volatilization losses were small after mowing field peas in dry conditions. Can. J. Soil Sci. 93: 239-242. Ammonia losses following termination of peas (Pisum sativum L.) by mowing were measured using a micrometeorological mass-balance approach. Field trials were conducted during two seasons in a semiarid climate. Plant N in the above ground biomass was 105 and 79 kg N ha^-1 in 2011 and 2012, respectively. Vertical NH₃ flux estimates were nominal (0.3 to 1.7 g N ha^-1 h^-1) in the 2 wk following mowing. Cumulative NH₃ loss represented 0.3 to 0.5% of the N in plant biomass, indicating that N fertility was not diminished by NH₃ volatilization in this dry climate.