What to spray on timber cut over to stop regrowth

I'm having some timber cut and I won't be able to clear stumps this year for sure.

 

A good many of the trees are along terraces between hay fields.

 

Question is, once the stumps start to regrow what would be best to spray them with and not hurt the grass in the area...

 

I will be working the edges along the stumps & grass this summer and attempt to keep growth down as best as I can....

 

I have posted a aerial pic for reference before the cut..

 

Thanks, Chris

 

What to spray on timber cut over to stop regrowth