For our purposes I would bet there is very little difference between the soil building properties of the cereals. I have always heard rye is the king of cover crops, and it probably is. But that throne is a little overblown. If we had one rye plant, one wheat, and one oats plant to dig up, I doubt any of use would notice much difference. They would all be a big time pain to dig up. On many of these forums many don't give enough credit to oats and wheat for their abilities to "mine" nutrients and add OM. They are very good at both, if you don't believe me try to dig a plant up and see how easy it is ;) They all have extensive roots, and those roots are all efficient miners.
Just like smith I don't plant wheat because the seed is more expensive in my area. I can get rye for $9/ bushell, and oats for $6. Cheapest wheat I've seen is $22.
Woods doesn't have a clue. Of the 3 oats will smother and kill newly established alfalfa and clover. I've seen this in wet years, when it falls over. Oats has alot more leaf to it when it matures compared to rye, which has alot more stalk. I've been growing both of them as a cover crop for decades. I leave mature rye all the time in food plots, and have yet to see it smother baby clover or alfalfa. I wouldn't do it with spring planted clover/alfalfa with an oats cover crop. Planting it that late in the season will give you little growth anyway, unless you are way south.
Wisc this makes no sense. If wheat "needs" more nutrients to grow, it's going to scavenge more nutrients from the ground, and process those nutrients into organic material (ie-roots, plant material, grain). I'm sorry but this information is misleading. The process is a cycle. Nothing leaves the cycle unless it is removed, which can happen in a variety of ways.
However, at the end of the day we are splitting hairs debating which one is better than the other. We should all agree they are great deer food, and soil builders. Since the food plotter isn't removing the grain or the plant material, over the long run, the soil is improving with all 3. It's likely rye is just a little better than the other 2 at soil building, but that difference is really irrelevant if everythings going back into the soil anyway.
I'm opening up my wallet this year and gonna grow all 3 together.