Sounds like they might be imported cabbage worms. (Imported from England, thank you very much.) Other control methods I've heard about in addition to the more effective ones stated above: Spread corn meal around the plants (the caterpillars are supposed to eat it, swell their stomachs, and die) Catch the moths with a butterfly net Get kittens who love to catch the moths and eat them :) Before eating the leaves, soak in salt water (so the caterpillars will die and fall off and you won't have to eat them.) DEFINITELY more of a problem with weak plants. I had kale growing two different places, one with much better soil. The caterpillars barely noticed the healthier plants, and they had apparently gotten under my row covers over the less healthy plants, and the result was an absolutely comical stripping job (I could laugh because I had the healthy kale in the other bed :) ) I've had kale plants produce for years without bolting or flowering, so you may well find a nice spring crop of collards growing from the old stems. Also, when it gets cold is when those nasty things finally die, and you get pest free leaves again! Next year try waiting before you cut the plants and see if the leaves clear up.

Either of those methods will work.... just as long as the seeds have developed you can dry them. I would recommend removing them from the pods though. Happy Couponing, -Kristina K. Here is a link that might be useful: Urban Farm Wife

I don't really understand which response was 'snarky.' Has something been deleted? cadred46 are you the OP with a new name? If not I don't follow your contributions. If you are you referring to the photos at the top of the post and saying the bugs were white flies, then Fori is absolutely correct. They are not whiteflies, they are aphids, and neither white flies nor aphids are physically capable of making those holes. Responders who suggested slugs, snails or, most likely caterpillars, were on the right track.

So the black rot is what I see in your first few pictures. What's the "second stuff"? You mean the eaten leaves? Probably cabbage worms. They bore holes in leaves. But what do you mean by "wiped off"? You mean in the last picture where part of the leaf is green, and the whitish coating is gone? That was wiped? Looks like powdery mildew. That's treatable. I wouldn't eat powdery mildew, but you can wipe if off, and kill the rest with hydrogen peroxide and vinegar.