I'm no expert, but if I had to wager a guess, it would be because of the weather. Winter in NY is harsher and longer than say, VA,KY,TN, or WV. So a shortened growing season followed by a realistically too short of a harvest season all would factor in. I know I will catch flack for saying this but again, the buyer I sell to in WV is able to tell the difference in ginseng by looking at it. He can tell if it is from, NY, WV, TN or wherever. He says the best ginseng is NY ginseng. Followed by Wisconsin, then WV, Then KY, then Tennessee. I would have to bet that it is all climate related.