Wasps Are Great At Controlling Cabbage Worms - They Eat Them

If you see a wasp crawling around on your Cabbage, Cauliflower, Broccoli, or Brussel Sprouts, they are probably looking for worms to eat. They love to eat Cabbage Worms and Cabbage Loopers.
Of course, you should keep your distance from wasps, but if you don't mind them being in your garden, they can help you out by eating the worms that eat your Brassicas.