This term applies to herbs which are sourced in the wild. This can mean a lot of things to a lot of people, so here are some greater details:
The herbs sourced this way are bound to a set of stringent guidelines, which include rules such as having to be located a certain distance from businesses, industries, and roads; they truly are in the wilderness.
This does imply that they would also be non-GMO, organic, and free of any pesticides, though because these plants are not grown in a controlled environment, we can not claim that they are such.
Another note: wild herbs are provided to manufacturers in their complete plant form, which allows the purchaser of these ingredients to be able to assess the quality of the herb prior to sale or use.
Please rest assured that these plants are just as high quality as those which are obtained from nurseries/growers, and this is a sustainable practice!.