Rather odd question.
Locally, I can source oats for animal feed for 8$ taxes included for 25kg. Darn cheap. Almost as cheap as manure. I was wondering if it could be a good idea to sprinkle that into a rather poor sandy soil, to feed it? Or is it really dumb?
Excuse me while I theorize, someone here will probably chime in with a correction if my reasoning or understanding of some facts are wrong. I tend to be an information sponge which sometimes leads to me absorbing misinformation.
One of the reasons people sometimes object idea that beans can be grown as a crop and green manure, simultaneously is that the plant is supposed to use the extra nitrogen to build proteins in the seeds. If that rational is correct (at least in the idea that proteins are built with high amounts of nitrogen) then oats are probably an ideal way to add nitrogen into your soil ecosystem.
I used wheat over lawn (planted in late fall with the lawn cut real low) to out-compete lawn grass and would have got a nice harvest if it weren't for something else eating the seeds days before I would have. I think oats will winter-kill if you get to cold. Not sure what your weather's like, but as long as the seed is viable (not cracked or cooked or sillaged or anything), I'd think you could use it. I'm not sure of pesticide rules with animal feed, but if you are worried about GMO, you might also want to keep that in mind. If it is not viable, you'd be adding organic matter to the soil by putting it in there, but it would still have to decompose and since it is feed, you might be attracting all sorts of wildlife you might not want hanging out in your garden.
If those are whole, unrolled oats, the best method of use is to sow and let grow.
If they are rolled or crimped oats then you would get the best use by soaking them then lightly digging them in where you spread them, like they were fertilizer.
For mushroom growing medium, cook the oats, let cool then bag and inoculate. The reason for cooking is to gelatinize the starches.
Oats make a nice nurse crop for other plants, particularly if you plant them in the fall and let them winter kill. They don't fix nitrogen, even when inoculated with an appropriate bacterial inoculant.
As was stated above, you can crimp oats at the base and that will stop them from growing. On a large scale, a roller or crimper is pulled behind a tractor and flattens the oats all in the same direction, laying down a thick mat of mulch. On a small scale, using a scythe or just a pair of hedge clippers will cut the oats off at the base and drop the plant to the ground as a mulch. If you've got chickens, then you can run them through and they'll go crazy for those oats.
Here's a great article on cover cropping, including using oats:
I use cayuse oats as a part of my winter/cool season cover crop mix, along with hairy vetch, purple vetch, buckwheat, bell beans and tansy. It comes up in a big tangled mess -- all the better to feed the soil and provide winter habitat for my spiders, lizards, and other garden dwellers. By March, it'll be 4 to 5 feet tall—the great green biomass wall. I take the scythe (or my electric hedge trimmer) and knock the whole thing back in preparation for spring planting. Another benefit of growing a winter cover crop is that it keeps the temperature of the soil down so my stone fruittrees don't break dormancy too early.
Everyone should make a couple of mistake every year in order to learn something new. But those oats, sew them, and see what happens. If it's a flop, you'll learn, you aren't out too much money. It it's a hit, you'll learn and your garden will be all the better for it. Give it a shot. Tell us what happens.
"The rule of no realm is mine. But all worthy things that are in peril as the world now stands, these are my care. And for my part, I shall not wholly fail in my task if anything that passes through this night can still grow fairer or bear fruit and flower again in days to come. For I too am a steward. Did you not know?" Gandolf
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