We have huge issues with herbicide resistant grass weeds, mainly black grass and rye grass. Slight change of cultivation practice this year, so we didn't plough the wheat stubble as usual which buries the weeds and anything blown off the back of the combine so we didn't plough any weed seeds back up. Stubble will be sprayed with roundup to burn off weeds and volunteers, but the grass weeds take ages to germinate, by which time, all of the other weeds are enormous! Our drill doesn't like trash, so I drilled it without tramlining at an angle so the weeds and volunteers left by the combine wer going through the drill at an angle and not blocking it up.

The drill is an air drill with a single metering unit. The seed is metered into the path of air in a tube and blown to the coulters. On either 2 or 4 (one or 2 for each wheel mark, I forget now), there is a electric flap that blocks the appropriate tube to get the track width spacing correct. When the drill tramlines, which is sequenced by the bout markers, the flaps close which leave to unplanted rows. It's a drill operators favorite pass time to drive around the country looking at who had problems the the tramlining on the drill and laugh at them yet be secretly relieved they didn't screw up. It's written in EU law that these mistakes only happen when the field is visable from the road and extra points are awarded when the field is next to a busy road, or ideally next to a busy road and on a bank for more people to see your mistakes. One of my sepcialities is putting randome tramlines in when doing headlands, these I refer to as "trials".

This is the latest version of our drill

https://uk.kverneland.com/Kverneland-Seeding/Seed-Drills/Kverneland-ts-drill