Thena I know the larger plant is primrose and the Eraser will take care of that. I'm not sure what will take care of the duckweed though, possibly the same although the active ingredient that the TAMU site recommends isn't the same. I'd try the Eraser on the primrose first and see if it kills the duckweed. Too bad you can't let the wind "congregate" it all at one end then have the wind die down so y'all can get it easy.
