What rate are you mixing your gly for these results? Are you traveling at a higher rate of speed when spraying?
I haven’t experimented with it yet but I’ve seen numerous other folks report that they’ve had clover come back after spraying it. It a pretty tough plant. If I were going to test it I would probably try something like ½ quart per acre.
What summer plantings do you find more beneficial to the wildlife than established clover?