Although many online stores martket "Wild American Ginseng" or "Wild Wisconsin Ginseng", it's hard for the average consumer to determine its authenticity.
When you decide to invest or purchase a Wild American ginseng, the Rule of Thumb is " Do not buy it if you do not seee the full Rhizome or root-neck with less than 5 scars (no less than five years old)!" Cultivated ginseng usually has less than 5 scars (five years old). Wild ginseng has to be at least five years old before harvest. Some wild-simulated roots (grown like wild with planted seeds and under no human care) may have more than five scars, at least you are getting a more naturally-grown ginseng.
Here is how you count the scars of the root-neck
Here is An Article on Age of Wild Mountain Ginseng from USDA