Need some help selecting a herbicide to spray around my chicory. I planted about an acre of chicory 2 seasons ago, the first season it didn't do so great, last season it did very well and all I did was mow/bush hog over the top of it to help with the competing weeds and grasses, this year oh baby it has come in much thicker but there are still some competing grasses in the mix that I would like to get out of the way. At the rate I 'm going I could have a well manicured area of chicory but I want to get a jump on the competing grasses.

The main type of grass I'm seeing right now is about a foot tall and has a seed head already but it is not johnson grass. Any advice on a good herbicide to use that won't kill my chicory would be a big help!
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"The world is so dreadfully managed, one hardly knows to whom to complain."
-Ronald Firbank