I would go ahead and water cure that moldy bud. You are going to have to go through about a week of it though. My very first harvest of 10 ounces went to mold because I jarred too early and never let it air out properly after. I water cured the entire lot and I still have some today, jarred up and smokeable. In fact, in my opinion, it made the bud look better. Check out the pic below, the bud on left was water cured, the one on right is exact same strain, 2nd indoor harvest.
Many people will tell you NOT to smoke that weed, I on the other hand have actually experienced mold and have researched and found this cure for it. I've only had to do it one, and I hope to never HAVE to do it again. Also, mold spores cannot travel in smoke. The U.S. Government did a study due to concerns of the Congress that mold in tobacco could harm the smoking population. (mold in tobacco is VERY common) After 2 studies, it was determined that there was no additional health risk associated with inhaling smoke from tobacco with mold on it, other than the harmful effects of cigarettes themselves. Any doubters can Google away.
Anywho, water cure the bud and your mold is gone. Smoke will be smoother too, a lot smoother. The only reason I don't water cure on a reg basis is because it kills the bud's aroma. Taste, oddly enough is not affected as much, but the buds lose their wonderful aroma. This can be a good thing if you have to ship a package or pack a vehicle for a trip. I'm sure a trained dog might still pick up on it, just pack weed into center of car and never give permission for a search and you are golden. They won't smell it.
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