What is the significance of the vision that Frank has in chapter 26 when he goes out riding?

Frank goes out onto the land, watching the sun set across the valley, closing his eyes. When he opens them, he sees the ghostly shape of people riding horses through the trees, of women gathering herbs and berries. Frank raises his hand to the idea of his mother and father and a line of people he’s never known. He then rides back to the farmhouse, where the old man is waiting. In the very last pages of the novel, Frank also comes to know his ancestors through the land. The final chapters of Medicine Walk return to and reiterate the thematic importance of land within the novel, as the land connects Frank to generational knowledge and to his family.