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A common plant pathogen, <i>Acidovoraxavenae</i> subsp. <i>avenae</i> (<i>Aaa</i>) has recently been found in association with an emerging disease on creeping bentgrass (<i>Agrostis stolonifera</i> L.) causing unique symptoms of etiolation and decline. First reported in 2010, <i>Aaa</i> has since been isolated out of more than 20 different symptomatic golf course samples. Identification via 16S rDNA sequencing and inoculation studies have confirmed pathogenesis of <i>Aaa</i> on creeping bentgrass. Temperature range studies show disease progression to be most severe at 30-35°C under high relative humidity. All creeping bentgrass cultivars inoculated thus far with 2.0 x 10⁸ CFU of <i>Aaa</i> have been susceptible to infection when compared to sterile buffer control inoculated plants. Field studies and subsequent growth chamber studies on creeping bentgrass were conducted in order to elucidate potential chemical management options. Oxytetracycline pre-treated at 200 ppm significantly reduced leaf necrosis, discoloration, and thinning after inoculation with <i>Aaa</i> at 2.0 x 10⁸ CFU compared to an untreated, inoculated control (P < 0.001). This is the first study elucidating <i>Aaa</i> infection on a commodity turfgrass in the United States. Genetic characterization of <i>Aaa</i> to closely related plant pathogenic <i>Acidovorax</i> spp. via multi-locus sequence typing (MLST) is underway with plans for genome sequencing of the turfgrass pathogen and the development of a molecular diagnostic assay.<p><p>Keywords: Bacteria-Phytoplasma-Spiroplasma-Fastidious Prokaryote, Turfgrass, Cool-season