I've got some old pastures that I've decided I'd rather plant than mow. They have broomstraw growing and I'm trying to decide whether to burn them before first discing or just disc in the organic matter. Mostly sandy loam soil. I may also spray them with roundup before discing just to kill the grass quicker. What's the conventional wisdom? Is it better to just disc over and over or first get rid of some of the chaff? One advantage of burning is that it will give me one or two more of the burns I need to log for my burn manager cert.

When discing, is there any value in discing deep or should I just go deep enough to cut the roots?

Any other questions I didn't know enough to ask?