Johnsongrass in Tefff

I've got a couple of fields planted with Bonus Teff this year in transition before adding a little bit more AU Grazer lespedeza acreage.  The teff was planted 4 weeks ago, with poultry litter applied before discing/smoothing/packing.  One field, I have a significant mix of johnsongrass in. 

Any thoughts on control options?  I know herbicide labeling for use in Teff is very limited.  Am I limited to a weed wiper over the top here, as I've got a summer annual grass over a summer annual grass? 

Did a search and didn't come up with any real responses to this particular combination.

 

Thanks for your thoughts. 

 

Reed

Johnsongrass in Tefff