The data document the results of several microbe bioassays performed by the USGS on Phragmites australis plants, including those performed on mature leaves, seedlings, and dead leaf tissues exploration of the literature to find accounts of microbes associated with Phragmites worldwide. For the bioassays, we prepared 162 pure cultures isolated from Phragmites plants in North America along the east coast, Florida, the Gulf of Mexico, and the Great Lakes area, 125 of which were from a previous study, and 38 represent new collections. The DNA sequences used to identify the 37 new collections are included. Microbes were isolated from plants collected from 2015-2018. We performed assays using both North American plant lineages (Phragmites australis subsp. australis and Phragmites australis subsp. americanus) on mature leaves and seedlings. Data included here report each plant's reaction to microbial inoculation. Finally, to put our findings in context, we surveyed Phragmites-associated microbes assembled from multiple extensive literature sources representing a worldwide extent These data will be valuable to researchers interested in effects of leaf microbes on Phragmites health and invasiveness of the non-native lineage. Additionally, the data have implications for potential biocontrol of Phragmites.