Is it possible to place the seed in a narrow slit without spillover?
With good quality zero-till-ferti-seed drill, generally, all the seed and fertilizer can be placed in the narrow slit. Some seed could still be falling outside, in vicinity of the slit, depending upon roughness of the fields and the speed of the tractor. All such seed if not picked by birds will germinate after a post sowing irrigation. In the presence of anchored/standing residues of the previous crop or mulching with a shrub master it is often difficult o pickup the seeds from the spilled over seed.