BigRoots,
Good luck on all of the new emerging and already emerged plants and planting this fall! I hope that you soon have Ginseng plots to be proud of and that will bring some monetary return within a few years! From the pics of the 3 and 4 prongers, it appears that within a few short years, you will no longer have to purchase Ginseng seeds for new beds and will be able to harvest what you need from your' own plants. That in itself, is extremely beneficial in making Ginseng growing a profitable venture!
I know that hilling up the plants for protection from the weather extremes will make it somewhat difficult when the time comes to harvest some plants! However, the benefits of having the plants and their' roots survive and having good seed production, will outweigh any difficulty in harvesting in the years to come. I will make one more point to the method that I recommended, then leave it to you and nature to provide you with great Ginseng plants, root growth and great seed production. If the soil is fairly loose around each plant or can be loosened somewhat without disturbing the roots, the hilling up of rich loose soil around the plants will give the roots much more room and ease to expand and grow but especially for new roots fibers to grow. This will not only add weight to the roots for when it comes time to harvest, it will also aid in having much healthier plants and roots as the extra fiber growth will be able to pull in more nutrients and moisture.
Although I really can't recommend placing straw in the bottom of the holes for plant hills that you have dug to plant any Ginseng roots, this method is extremely beneficial when planting seed potatoes. Potato plants produce 5 times as many potatoes (i.e. tubers to the potatoe plant roots) or more per each hill when planted in this method and the same should aid Ginseng root growth as well! Since I have never heard of anyone trying this method with Ginseng, so I really can't recommend it but maybe a few test hills planted with Ginseng in this way, could not hurt and might prove to work. If you happen to try this, I would advise to not use a whole lot of straw in the bottom of the holes in each hill, as straw produces a lot of heat as it rots and degrades, and too much heat could actually harm the Ginseng roots. The other problem is with straw and weed growth that might come with this method due to seeds in the straw. However, once the Ginseng plants have established good root bases, the straw and weeds can be weeded out.
Good luck and please keep us updated on any and all progress! Oh and I almost forgot to ask for some pics showing the type of terrain you are planting in. I know that much of Iowa is flat with some rolling hills and low ridges in some locations except in the Northeast and along the Mississippi River where the terrain is more rugged with some higher ridges and bluffs. The pics may help others planting in similar terrain and will also give us some reference for future advice!
Frank