pecan (Carya illinoensis)
Carya oliviformis (Michx. f.) Nutt.
Carya pecan (Marsh.) Engl. & Graebn.
Hicoria pecan (Marsh.) Britton
CONFIRMATION STATUS: Confirmed.
TAXONOMY: The currently accepted scientific name for pecan is Carya
illinoensis (Wangenh.) K. Koch. There are no recognized subspecies, vari-
eties, or forms. Pecan hybrid products are: 1) Carya illinoensis x Carya
aquatica=Carya X lecontei Little, 2) Carya illinoensis x Carya laciniosa
=Carya X nussbaumeri Sarg., 3) Carya illinoensis x Carya tomentosa =
Carya X schnecki Sarg., and 4) Carya illinoensis x Carya cordiformis =
Carya X brownii Sarg.
NATIVE STATUS: Native, United States.
GENERAL BOTANICAL CHARACTERISTICS: Pecan is a long-lived,
medium to large, native, deciduous tree ranging from 100 to 150 feet (30-
45 m) in height and 6 to 7 feet (1.8-2.1 m) in diameter. The gray trunk is
shallowly furrowed and flat-ridged with ascending branches forming an
irregular, rounded crown. The twigs are gray brown and hairy when young
but become rough and furrowed on mature trees. Flowers are borne in sta-
minate and pistillate catkins. Staminate catkins are in threes and bear small
green flowers; seed-bearing flowers occur singly or a few at the end of new
growth. The leaves are narrow, pointed, and curved at the tip with tooth
margins yellow-green above and paler below. The nut is brown, cylindric,
thin-shelled, and enveloped in a four-winged husk.
REGENERATION PROCESSES: Seed production starts when the trees
are about 20 years old, but optimum seed-bearing age is 75 to 225 years.
The trees bear fair to good crops almost every year. A mature tree yields
about 100 pounds (40 kg) of nuts per year. The seed is disseminated by
water, squirrels, and birds.
Under normal conditions, pecan nuts remain dormant until germination
starts in early April. Exceptionally dry weather or heavy competition great-
ly reduces seedling survival. Under favorable condition, pecan seedlings
grow 3 feet (0.9 m) per year after they have been established for several
Small stumps and fire-girdled seedlings and saplings sprout very rapidly.
Horticultural varieties of pecan are propagated by budding and stem
SITE CHARACTERISTICS: Pecan is most common on well-drained
loamy soils not subjected to prolonged flooding. Throughout its range it is
largely limited to bottom alluvial soils of relatively recent origin. Its best
development is on riverfront ridges and well-drained flats. It rarely grows
on low and poorly drained clay flats; it is usually replaced by water hickory
(Carya aquatica) on these sites.
SUCCESSIONAL STATUS: Pecan is classified as shade intolerant but is
more shade tolerant than cottonwood or willow. It responds well to release
in all age groups, provided that the trees have good vigor. Pecan is a sub-
SEASONAL DEVELOPMENT: Pecan flowers from March to May about
a week after the leaves have started to open. The nuts mature from Sep-
tember to October; seedfall begins in September and ends in December.
GENERAL DISTRIBUTION: Pecan grows principally in the bottomlands
of the Mississippi River valley. Its range extends westard from southern
Indiana through Illinois, southeastern Iowa, and eastern Kansas, south to
central Texas, and eastward to western Mississippi and western Tennessee.
Pecan occurs locally in southwestern Ohio, Kentucky, Alabama, and central
Mexico. Its best commercial development is on river-front lands of the
Mississippi Delta and along major rivers west of the Delta to Texas. Pecan
is cultivated in Hawaii.
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: Pecan prefers
rich moist soils of bottomlands, especially along the sides of streams.
It can also be found in deciduous forests.
Common tree associates of pecan include slippery elm (Ulmus rubra),
sugarberry (Celtis laevigata), box elder (Acer negundo), silver maple
(Acer saccharinum), roughleaf dogwood (Cornus drummondii), and
swamp-privet (Forestiera acuminata). Common understory components
include pawpaw (Asimina triloba), giant cane (Arundinaria gigantea), and
pokeweed (Phytolacca americana). Vines often present are poison-ivy
(Toxicodendron radicans), grape (Vitis spp.), Alabama supplejack
(Berchemia scandens), greenbriers (Smilax spp.), and Japanese honey-
suckle (Lonicera japonica).
IMPORTANCE AND USES: Pecan nuts are eaten by a number of bird
species, fox and gray squirrels, opposums, racoons, and peccaries. White-
tailed deer sometimes heavily browse older pecan trees.
Pecan provides cover for a variety of birds and mammals in the oak-hick-
ory forests of southeastern United States.
Pecan has been successfully planted on surface-mined lands of Indiana,
Oklahoma, and Missouri. The deep, lateral roots can provide excellent
Pecan wood is inferior to that of other hickories and is not important com-
mercially. It is occasionally used for furniture, flooring, agricultural imple-
ments, tool handles, and fuel.
Pecan is widely planted as an ornamental, and for its sweet edible nuts.
The nuts have a high percentage of fat and are used extensively in candies
and cookies. The leaves and bark are sometimes used as an astringent.
Crooked Run Valley