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Turbulence statistics and blade deformations of flexible emergent canopies impinged by water flows were experimentally investigated across a range of Reynolds numbers Reb=Ubb/ν (where Ub is the bulk incoming flow velocity, b is the blade width, and ν is the water kinematic viscosity) and blade aspect ratios AR=h/b (h is the blade length). Time-resolved particle image velocimetry was used to characterize both the deformation of flexible blades and the surrounding flow fields. Results showed that the blade deformation increased with the growth of both Reb and AR, with higher blade bending causing stronger variations in vertical profiles of streamwise velocities and Reynolds stresses. The drag produced by the presence of flexible canopies was identified as the dominant fluid loading balancing the pressure gradient. This term exhibited distinctive reduction near the water surface region with high blade deformation due to the large local blade inclination angle. Interestingly, in contrast to fully submerged flexible blades where the flow-induced drag increases monotonously with flow speed, a critical Reynolds number Reb,cri was observed, beyond which drag decreased with increasing flow speed until the blade became fully submerged. This phenomenon was explained with theoretical interpretations, which exhibited reasonable agreement with experimental results. Further analysis of unsteady flow dynamics revealed that Reynolds stress within the canopy was dominated by ejection events due to the absence of shear layer at the top of emergent canopy. Additionally, streamwise velocity spectra indicated that flow fluctuations inside the canopy were governed by periodic vortex shedding from blade.