Article about the Algonquin to Adirondack Conservation Association (A2A) in Canada. This organization is trying to preserve old growth forests in part to protect wild ginseng in Canada, which requires particular environmental conditions:

"At one time, exports of wild ginseng from Ontario and Quebec rivalled the fur trade. But by the late 1800s, most of the wild colonies were gone and domestic plants were grown instead. Now, there are only 65 sites of wild ginseng that have been identified in Ontario, but only 15 of those sites have the minimum number of 172 plants needed to ensure a colony's survival. The average population of a colony is 10 to 20 plants.

Wild ginseng has demanding requirements: a closed canopy in an old forest, preferably on a slope under sugar maples; moist soils throughout the growing season; good drainage close to streams or wetlands; and undisturbed leaf litter.
Then it takes seven to 15 years for a plant to reach maturity. If it survives, it can live for 50 to 60 years. But cut the trees, and let the sun dry the soil, or disturb leaf litter, and it dies or never germinates from seed."