bitternut hickory (Carya cordiformis)
Carya cordiformis (Wangenh.) K. Koch var. latifolia Sarg.
Hicoria cordiformis (Wangenh.) Britton
CONFIRMATION STATUS: Confirmed.
TAXONOMY: The currently accepted scientific name for bitternut hick-
ory is Carya cordiformis (Wangenh.) K. Koch. There are no recognized
subspecies, varieties, or forms. Bitternut hickory naturally hybridizes
with the following: 1) Carya illinoensis (Carya X brownii Sarg.), 2) Carya
glabra (Carya X demareei Palmer), 3) Carya ovata (Carya X laneyi Sarg.).
NATIVE STATUS: Native, United States and Canada.
GENERAL BOTANICAL CHARACTERISTICS: Bitternut hickory is
a medium-to-large native, deciduous tree, typically reaching a height of
60 to 80 feet (18-24 m). Under a forest canopy, it develops a long branch-
free trunk with little taper, and a short rounded crown of slender ascending
branches that broaden the crown toward the top. The branchlets are sparse
and tend to droop slightly from the main ascending branches. The leaves
are long and slender.
REGENERATION PROCESS: Bitternut hickory does not produce abun-
dant seed until the tree is approximately 30 years old. Optimum seed pro-
duction extends from 50 to 125 years; trees that are more than 175 years
old seldom produce seed crops. Good seed crops appear at 3- to 5-year
intervals, with light seed crops borne in the intervening years. Bitternut
hickory seed is estimated to be from 75 to 85 percent viable. Seed dissem-
ination is almost entirely by gravity.
Bitternut hickory is the most prolific rootand stump-sprouter of the north-
ern species of hickories, with sprouts arising from stumps, root crown, and
roots. Most sprouts from sapling and pole-size trees are root crown sprouts,
while those from sawtimber-size trees are mostly root sprouts. Stump
sprouts are less numerous than either root crown sprouts or root suckers.
SITE CHARACTERISTICS: In the northern parts of its range, bitternut
hickory occurs on a variety of sites. It is found on rich, loamy or gravelly
soil, low wet woods, and along borders of streams, but is also found on dry
uplands. In the south, bitternut is more restricted to moist sites than in the
north. It reaches it largest size on the rich bottomlands of the lower Ohio
River Basin. In the southwestern parts of its range, bitternut hickory is
common on poor, dry, gravelly upland soils. Bitternut hickory is absent
from the mountain forests of northern New England and New York, and
it is not found at the higher elevations in the Appalachians.
SUCCESSIONAL STATUS: Bitternut hickory are generally classified as
intolerant of shade but bitternut hickory seedlings appear to be more tol-
erant on overflow bottomlands than most of its associates. Top dieback
and resprouting may occur frequently with each successive shoot attaining
a larger size and developing a stronger root system than its predecessor.
By this process, hickory reproduction gradually accumulates and develops
under moderate canopies, especially on sites dry enough to restrict repro-
duction of more tolerant, but more fire- or drought-sensitive species.
SEASONAL DEVELOPMENT: Bitternut hickory flowers in April or May.
The fruit ripens in September and October and is dispersed from Septem-
ber through December.
GENERAL DISTRIBUTION: Bitternut hickory's range extends from
southwestern New Hampshire, Vermont, Maine, and southern Quebec;
west to southern Ontario, central Michigan, and northern Minnesota;
and south to eastern Texas and northern Florida. It is most common
from southern New England west to Iowa and from southern Michigan
south to Kentucky.
SKY MEADOWS DISTRIBUTION:
Tree specimens can be found on trails marked in red.
Appalachian Trail/Old Trail
South Ridge/North Ridge
Rolling Meadows/ Lost Mountain
HABITAT TYPES AND PLANT COMMUNITIES: Bitternut hickory
grows in moist mountain valleys along streambanks and in swamps.
Although it is usually found on wet bottom lands, it grows on dry sites
and also grows well on poor soils low in nutrients.
Commom tree associates include eastern hophornbean (Ostrya virginiana),
butternut (Juglans cinerea), and hackberry (Celtis occidentalis). Common
understory associates include largeflower bellwort (Uvularia grandiflora),
Virginia creeper (Parthenocissus quinquefolia), wood-nettle (Laportea
canadensis), and violets (Viola spp.).
IMPORTANCE AND USES: Bitternut hickory fruit is generally consid-
ered unpalatable to wildlife. Rabbits, beavers, and small rodents will
occasionally feed on the bark of bitternut hickory.
Bitternut hickory provides nesting sites for a variety of cavity-nesting
The deep lateral roots of bitternut hickory make it a valuable species for
watershed protection. Bitternut hickory has been grown successfully on
zinc mine waste sites in southwestern Wisconsin.
The hardwood of bitternut hickory is used for making tools, furniture,
paneling, dowels, and ladders. Bitternut hickory is also desirable for
charcoal and fuelwood.
Smoke from the wood of bitternut hickory is used to give hams and bacon
a "hickory smoked" flavor.
Early settlers used oil extracted from the nuts for oil lamps. They also
believed the oil was valuable as a cure for rheumatism. Bitternut hickory
is desirable as an ornamental or shade tree, and the dense root system
provides good soil stability.
Crooked Run Valley