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Abstract. The effectiveness of agriculture spraying systems is greatly dependent on interactions between the droplets and the leaf surface of the sprayed plants. These interactions influence droplet adhesion, spread, or rebound, and are determined by the physical and chemical properties of the both the droplet and the leaf. This paper presents preliminary results of an ongoing study investigating the effects of leaf surface hydrophobicity, cuticle wax load and composition, surface roughness, and trichome density on the adhesion of impacting water droplets. The study also considers the effects of droplet size, composition, and impact velocity. Droplets were produced by a single mono-sized droplet generator and a streamed mono-sized droplet generator mounted on a horizontal motion track. Speed is varied by the track and release height from the surface. Droplet motion and surface interactions were recorded with two Ultrahigh-speed cameras and analyzed with 3-D motion analysis software. Hydrophobicity was determined by sessile drop methods. Wax load and composition was measured gravimetrically and with contact angles. Roughness was determined using a 3D optical profiler. Trichome density was measured with imageJ analysis software. Plant leaves reported for this study include B. Oleracea 'Cabbage', C. Annuum 'Jalepeno', A. Graveolens var. graveolens, O. Basilicum, Z. Mays, C. Pepo 'Yellow crookneck', and G. Max.