Ginseng with only the main stem and usually three leaves growing at the top are called Flat Tops. While Flat Tops generally have three leaves, they will sometimes have four or five leaves. Four leaves on a Flat Top are somewhat common while five leaves are not. The next time the plants come up, they will usually be Two Prongs but sometimes due to detrimental conditions, some may again emerge as Flat Tops. However, if the conditions are good and a plant has good genes, it might emerge as a Three Prong.
Frank