Seedlings from producing grafted Colossal chestnut trees in our orchard. They make a superior rootstock for all the many great chestnut varieties that are relatives of Colossal. They can be either grafted as seedlings, or better yet grown out in the field or large pot to at least 2" caliper size and then easily topworked to the desired variety. While Colossal seedlings make a nice strong tree on their own, their nut production quantity and quality wise is a shadow of what a grafted Colossal will do. Plan on topworking!.