I always plant whole oats, or, in other terms, oats that are designated for animal feed. Why? They are $14 per hundred vs $115 per hundred for seed oats. I've never had much of a problem with weed seed contamination, most of the contamination is bits of stems and corn kernels. At the price savings I can deal with a few weeds if any would show up, and since the deer can't read in my county because it's like a third world country, they think I'm planting BFO and they go plum crazy over them.