I dropped seed off this morning to a client and he asked me, "isn't all oats the same?" He mentioned that a coop guy once told him that. Here is my answer to that question based on my experiences as a nutritionist and seed specialist.
There is the following types of oats.
1) Bin run oats
2) certified seed oats
3) certified winter oats
4) certified forage oats
I have planted a variety of oats in oat trials twice in the last 3 years and have some perhaps over 20 different varieties of oats in the last 25 years and here is my answer to the leading question.
Bin run oats we do not know what the germ count is nor do we know how much weed seed is in the bag. There could be perhaps 10 times the weed seed in a bag of bin run oats as certified and it might also contain noxious weeds. Bin run oats could have 90% germination count or it might contain 5% germination count. I have had people plant bin run oats and have nothing grow at all. Why take the chance on poor germ or high weed counts just to save $5 a bag?
Certified seed oats. There are 100's of different varieties. The biggest oat programs in the nation come from the Dakota oat, Minnesota oat and Wisconsin oat programs because of their weather. The varieties range from early maturing to late maturing. Some might average 32" of height and others 40" of height. Some have poor disease packages and others great disease resistance. Lastly, some out yield the others by 25% in grain production. Many grain oat varieties that are early maturing are shorter and don't make as good of forage.
Certified winter oats. Many people are aware of buck forage oats and plot spike oats. They are winter oats but that doesn't mean they will live to make it until spring. They typically can withstand 4-6 degrees colder of temperatures than traditional oats. That might give one a few extra days of green growth or it might mean no extra days if the weather plunges. Some of these winter oats do not carry over very well through the winter in bags so buy fresh seed. Some of these winter oats have light test weight, average germination and in some cases contain noxious weeds. Check the seed tags. The poorest quality oats ive ever seen has traditionally been the winter oats.
Certified forage oats. Forage oat are typically later maturing and taller. They produce as much as 25% more forage growth than the average certified grain oats. Some of these varieties also contain 5-10% more crude protein. A couple varieties I sell that have tested the best are goliath and forage plus oats. I am comfortable putting them side by side against the popular deer on a bag oats and you will see they yield better, have better germination count and the price per bag is $10-15 less than the fancy bagged winter oats. Sure you might see 4-5 days less frost tolerance but yield wise i'd say you will see no yield drag or difference between those and the winter oat brand.
The attached picture shows what happens when you roll the dice on oats. This is a grain trial done a couple years ago where there was 5 varieties of oats planted and 1 of the popular oat brands didn't do so well. The next year a number of businesses stopped handling that brand as their clients reported some of the same issues that i saw in the test plots.