According to Sargent this is the most widely and generally distributed, also the most variable in its fruit, of all the hickories. It is most closely related to the pignut (C. porcina, now called C. glabra), but that species has a nut with a usually bitter, astringent kernel, whilst that of C. ovalis is sweet and edible. It is a tall tree, often well over 100 ft high, with young shoots at first scurfy and downy, afterwards glabrous. The leaves consist of five or seven leaflets, which are lanceolate to oblanceolate and obovate, the terminal one up to 6 in. long, the lower ones down to 3 in.; all are finely toothed and at first scurfy and downy like the young shoots.
Native of the eastern United States from New York south to Florida. It has apparently been in cultivation as “C. microcarpa” and “C. porcina var. microcarpa”. The taxonomic position of this species is disputed. Some American botanists merge it into C. glabra; others consider it to be a hybrid between that species and C. ovata. Sargent made at least five varieties of this hickory, which is very variable in size and shape of nut. A tree at Kew introduced as C. ovalis var. odorata measures 72 × 51⁄2 ft (1963).
From the Supplement (Vol. V)
specimens: Kew, near Lion gate, 88 × 61⁄4 ft and 70 × 31⁄2 ft (1979); Eastnor Castle, Heref., 85 × 61⁄4 ft (1977).
The Kew trees are referable to var. odorata (Marsh.) Sarg., which is one of the many varieties of the red hickory that have been described. Apart from minor characters of the fruits, it differs in having the leaves somewhat glandular beneath.