Deed Restrictions and Conservation Easements
Deed restrictions "run with the land" (that is, remain in force no matter who owns the land or how many times it changes hands) and will protect it in the ways you have defined for at least twenty-one years.
Conservation easements can protect in perpetuity some portion of your land or all of it, as you choose. Particulars are worked out with whatever land trust or conservancy you gift, sell or otherwise convey your development rights to. Since the right to develop that portion of your land covered by the easement then belongs to a not-for-profit conservation organization, such land is permanently protected, so long as the organization or its heirs stay in business.
In North Carolina, conservation easements issue in both federal and state tax benefits that last for years. If land covered by such an easement is part of an estate, then upon the death of the owner, the estate tax may be significantly less. We can direct you to conservation easement tax experts who can definitively help with discerning what your tax benefit might be, were you to sell an easement.