NO 2 foliar deposition through the stomata of leaves has been identified as a significant sink of NO x within a forest canopy. In this study, we investigated NO 2 and NO exchange between the atmosphere and the leaves of the native California oak tree Quercus agrifolia using a branch enclosure system. NO 2 detection was performed with laser-induced fluorescence (LIF), which excludes biases from other reactive nitrogen compounds and has a low detection limit of 5–50 ppt. We performed both light and dark experiments with concentrations between 0.5–10 ppb NO 2 and NO under constant ambient conditions. Deposition velocities for NO 2 during light and dark experiments were 0.123 ± 0.007 cm s −1 and 0.015 ± 0.001 cm s −1 , respectively. Much slower deposition was seen for NO, with deposition velocities of 0.012 ± 0.002 cm s −1 and 0.005 ± 0.002 cm s −1 measured during light and dark experiments, respectively. This corresponded to a summed resistance of the stomata and mesophyll of 6.9 ± 0.9 cm s −1 for NO 2 and 140 ± 40 cm s −1 for NO. No significant compensation point was detected for NO 2 uptake, but compensation points ranging from 0.74–3.8 ppb were observed for NO. NO 2 and NO deposition velocities reported here are comparable both with previous leaf-level chamber studies and inferences from canopy-level field measurements. In parallel with these laboratory experiments, we have constructed a detailed 1-D atmospheric model to assess the contribution of leaf-level NO x deposition to the total NO x loss and NO x canopy fluxes. Using the leaf uptake rates measured in the laboratory, these modeling studies suggest loss of NO x to deposition in a California oak woodland competes with the pathways of HNO 3 and RONO 2 formation, with deposition making up 3–22 % of the total NO x loss. Additionally, foliar uptake of NO x at these rates could account for ~15–30 % canopy reduction of soil NO x emissions.