I went back re-read the posts on this Thread and want to comment on the problem with no companion plants sometimes after halfway up a mountain, ridge or hill all the way to the tops of these. There are a lot of reasons that this may happen and there probably is no way to list or even theorize all of them. Many times, I have seen this be the case of too much sunlight, not enough retained moisture in the ground (*), the location is in a rain shadow (**) due to higher Northwest to Southwest facing ridges and gets less of the much needed rainfall, many species of wildlife and especially Deer travel and bed in these locations and use these predominantly to get their' food sources and sometimes a series of intensely hot wildfires will devastate these species of plants and any seeds that they produced. With the latter two reasons, some companion plants will eventually come back up and/or these locations will eventually get seeded by birds and other wildlife over time. However, due to the former reasons, some areas may never really see much in the way of growth of companion plants while others may, especially if the canopy and moisture conditions ever become right.
While in many cases, with the lack of companion plants growing after halfway up a mountain, ridge or hill all the way to the top, no Ginseng will be found. However, this is not always the case. I have found Ginseng growing in these areas and even right out the tops of some ridges that were bare of almost all small plants except for the Ginseng itself. The reason why or how this could be, is fairly simple. Although our favorite culprit to blame for lack or loss of Ginseng is Deer but in reality, there are a lot more plants out there that they love and need more than Ginseng to survive and they will devour these first and when all of those are gone, then Ginseng is not far behind in becoming a meal. Yes, Deer often feed upon Ginseng earlier in the year and devastate our' crops or the wild plants but this is mainly due to the other plants that they need not being in these areas or these other plants have not matured enough to provide the Deer with what they need. If you walk the tops and higher ridges mountains enough, you will see what I mean. Eventually, you will come across Ginseng plants growing on or near the tops of the ridges of mountains with little if any other plants growing nearby. While it is somewhat of a dice toss as to whether you will find Ginseng growing in locations that are near bare or completely bare of companion plants, don't always discount the possibility of Ginseng being there! If these locations are not extremely hard to get to and search, it would behove you to have a look-see!
(*) This can often happen because the tops and higher sides of the mountains, ridges and hills are more susceptible to high winds that will often blow most of the ground leaf cover away and without the leaf cover to help hold moisture in the ground, the soil in these locations dries out too fast, leaving nothing for the smaller plants.
(**) A rain shadow is an area of dry land that lies on the leeward (or downwind) side of a mountain. Winds carry air masses up and over the mountain range and as the air is driven upward over the mountain, falling temperatures cause the air to lose much of its moisture as precipitation. Upon reaching the leeward side of the mountain, the dry air descends and picks up any available moisture from the landscape below. The resulting profile of precipitation across the mountain is such that rainfall and moist air prevails on the windward side of a mountain range while arid, moisture-poor air prevails on the leeward side of the mountain range.
Frank
