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Ammonia concentration and fluxes were measured above a growing triticale field for two months during May and June 2010 at the NitroEurope crop site in Grignon (Fr-Gri) near Paris, France. The measurement campaign started 15 days following a 40 kg N ha<sup>−1</sup> application of an ammonium nitrate solution. A new mini-wedd (Wet Effluent Denuder) flow injection analyser with three channels (ROSAA, RObust and Sensitive Ammonia Analyser) was used to measure NH<sub>3</sub> fluxes using the aerodynamic gradient method. The measured ammonia concentrations varied from 0.01 to 39 μg NH<sub>3</sub> m<sup>−3</sup> and were largely influenced by advection from the nearby farm. The ammonia fluxes ranged from –560 to 220 ng NH<sub>3</sub> m<sup>−2</sup> s<sup>−1</sup> and averaged –29 ng NH<sub>3</sub> m<sup>−2</sup> s<sup>−1</sup>. During some periods the large deposition fluxes could only be explained by a very small surface resistance, which may be partly due to the high concentrations of certain acid gases (HNO<sub>3</sub> and SO<sub>2</sub>) observed in this suburban area. Ammonia emissions were also observed. The canopy compensation point <i>C</i><sub>c</sub> was around 1.5 μg NH<sub>3</sub> m<sup>−3</sup> on average. The canopy emission potential Γ<sub>c</sub> (<i>C</i><sub>c</sub> normalised for the temperature response of the Henry equilibrium) decreased over the course of the measurement campaign from Γ<sub>c</sub> = 2200 to Γ<sub>c</sub> = 450, the latter value being close to the median stomatal emission potential (Γ<sub>s</sub>) and lower than the median ground emission potential (Γ<sub>g</sub>) for managed ecosystems reported in the literature. The temporal dynamics of the measured NH<sub>3</sub> flux compared well with the Surfatm-NH<sub>3</sub> model using fitted parameters. The subjectivity of the model fitting is discussed based on a sensitivity analysis.