That is really good-looking grain! We always seem to have an ergot grain here and there, but not enough to be problematic. Ours is all cattle feed anyway. I mean, too much of it can make the cattle sick too, but you know what I mean. :P

I vaguely recall my grandmother dumping the grain into a flat pan of pickle brine, and then whisking the bad grains off the top. But then it's all soggy and not good for much but porridge. :P

We don't grow too much grain, mostly barley and a little wheat, but when we have more ergot than usual we take a scoop of the grain out of the bin in a pitcher, spread it on a tarp, and pick out all the bad grains. Then we weigh both piles to determine the ratio, and assume that the whole grain bin has that ratio.

Crop rotation is key to preventing it. The spores (I guess?) won't live for more than a year, but if you keep planting the same grain in the same place, the ergot will keep coming back. They say you are supposed to plow everything under when you've gotten it, or it will keep coming back, but we seem to do ok with just a 4-year rotation between grain, corn, Sudex, and grass, and we sod-plant whenever possible rather than plowing and harrowing.