Laws Affecting the Herb Industry?

Are there many laws on growing, buying and selling, exporting, and wildcrafting? Other than ginseng and golden seal, can you sell herbs like hellebore, henbane, etc. as a novelty with a warning?

The primary law around wildcrafting is that you have a legal brush permit from the Forest Service, land owner, or other governing body on the lard you wish to remove items. Like firewood, you have to have a permit.
Very few items require a biohazard report when importing into the US. One of those that do, however, is ginseng. That is supplied by the buyer, declaring what he plans to do and where with the items in question.
Endangered plants must have a CITES document declaring it was legally harvested. That would include Hellebore. Since most things are endangered in Europe, a certificate of origin and a CITES document are always required.
A Schedule One permit is for controlled substances, such as henbane. As a plant, it is legal, as a pharmaceutical drug however, it has questionable intent. This would include hemp and mormon tea.