Hi there, I did some experimenting with no till in wheat stubble, and found the worst part for clogging up the seeder was the where the harvester wheels had laid over the stubble and l;eft it flat on the ground. I tried mowing the stubble ( a similar result to effective spreading) and I tried flattening the stubble with a heavy bar (railway line) and a scarifier with very wide points and set at ground level. All to no avail. The seeder still clogged. last try was to run a set of tandem offset disc harrows set 1 inch below ground level straight after harvest. This cut the straw, left it on the ground where it decomposed faster and by the next sowing date the seeder went right through without clogging. It also helped retain moisture in the soil. Another trick I have seen work is to leave the stubble standing and using RTK guidance, sow between last years rows.