Hickory nuts are perhaps the most delicious nut that can be grown in the Midwest, even surpassing the pecan for flavor in my opinion. In Missouri, we have two native species of hickories that make excellent eating: the shagbark hickory (Carya ovata) produces the most delicious nut while the shellbark hickory (Carya laciniosa) produces a much larger nut. Unfortunately very few of us have ever eaten hickory nuts because they are almost impossible to find commercially. Meanwhile, those who have harvested wild nuts usually find them extremely difficult to crack, yielding only tiny obliterated crumbs if and when they can be cracked. Several selections of both species have been identified, however, that produce large easily-cracked nuts that yield complete halves of sweet, delicious nut meats. Some cultivars may also have characteristics of disease and pest resistance, vigor, precocity, and annual bearing. An important draw-back in the commercialization of hickory nuts is that the trees are generally very slow-growing. We are therefore evaluating the hypothesis that the slow-growing shagbark hickory, which cannot tolerate periodic flooding on its own roots, may be able to grow faster on pecan (Carya illinoensis) rootstocks that thrive in fertile, moist flood-plain soils.

On September 30-31, 1997, fifty-five 'Peruque' pecan seedlings were planted in a 2.3-acre area of the Spring River bottom that had previously been seeded to orchardgrass. The trees are spaced 40 by 40 feet. In 2000, we began grafting a shagbark and shellbark hickory nut cultivar trial onto these pecan seedlings, with grafting continuing in 2004. Seven hickory cultivars selected for outstanding nut quality are being grafted with seven replications per cultivar in a completely randomized design. Six trees remain in the block for grafting additional hickory germplasm for evaluation. Additional pecan and hickory trees elsewhere in our nut plantation are also being grafted to other hickory cultivars as we develop a germplasm collection. The establishment of this study has been challenging with grafting success and scion survival less than desirable. After the 2004 grafting season, 35 of 55 trees (64%) are now successfully grafted, so that this long-term experiment is gradually becoming established. Domestication of the hickory nut is in its infancy and this small, long-term experiment will hopefully be a springboard for additional hickory studies, both at the Southwest Center and elsewhere.

Seven cultivars being evaluated in the Southwest Center's hickory variety trial: