Shellbark (Carya laciniosa). We have never had an opportunity to use this species as a stock. I think that it would make a good one and possibly be faster growing than shagbark.
Bitternut (Carya cordiformis). We have found that this species makes a very satisfactory stock for shagbark and hybrid grafts. We have not tried shellbark on it, except Berger which grows well on it. Seedlings of this species are much faster growing than are shagbark seedlings, and thus are large enough to graft sooner. We have grafts growing on bitternut stocks since 1935, they are growing and producing well. We consider this species as good or nearly as good as shagbark as a stock.
We have received contrary reports from farther south. These may be due to stock being blamed for something they did not cause or it may be that bitternut stocks grown from seed of more southern origin may not be as good as our northern stock.[18]
Pecan (Carya pecan). Our experience with this species as a stock is very limited and has been confined to grafts of only one variety of shagbark (Wilcox). Results were very disappointing, but we have been told by others that it makes a good stock. It is much faster growing than is shagbark.
Walnut
In walnut grafting, we have found that the eastern black walnut stocks are so much superior to any others we have been able to find, that we have discarded all others.
Butternut (Juglans cinerea). We have found that it is much harder to secure living grafts on this stock than on black walnut. It also attracts butternut curculio to the nursery.
Japanese Walnut (Juglans sieboldiana and variety cordiformis). We have found that seedlings grown from either of these species are a great attraction to the butternut curculio. They are more difficult to secure living grafts on, and grafts on these stocks are very definitely less hardy than similar grafts on black walnut growing side by side. We have proved this repeatedly.
Persian Walnut (Juglans regia). We have never used this species as a stock, and in view of the fact that grafts of it grow so well on black walnut stocks, I can see no use in even trying it.