Listing description
The pecan (Carya illinoinensis) is a
species of hickory native to Mexico and the southcentral and southeastern regions
of the United States.
Detailed description
"Pecan" is from an Algonquian word
variously referring to pecans, walnuts and hickory
nuts,[3] or more broadly to any nut requiring a stone to crack.[4] There are many variant pronunciations, some
regional and others not.[5] The most common American pronunciation is /piˈkɑːn/; the most common British one is /pɪˈkæn/.[5] Unusually, there is little agreement in the
United States, even regionally, as to the "correct" pronunciation.[6]
Growth
The pecan tree is a large deciduous tree, growing to 20–40 m (66–131 ft) in height, rarely to
44 m (144 ft).[2] It typically has a spread of 12–23 m
(39–75 ft) with a trunk up to 2 m (6.6 ft) diameter. A
10-year-old sapling will stand about 5 m (16 ft) tall. The leaves are alternate, 30–45 cm
(12–18 in) long, and pinnate with 9–17 leaflets, each leaflet
5–12 cm (2.0–4.7 in) long and 2–6 cm (0.79–2.36 in) broad.
A pecan, like the fruit of all other members of the hickory genus, is not truly a nut, but
is technically a drupe, a
fruit with a single stone or pit, surrounded by a husk. The husks are produced
from the exocarp tissue of the flower, while the part known as the nut develops from the endocarp and contains the seed. The
husk itself is aeneous, oval to oblong, 2.6–6 cm (1.0–2.4 in) long
and 1.5–3 cm (0.59–1.18 in) broad. The outer husk is 3–4 mm
(0.12–0.16 in) thick, starts out green and turns brown at maturity, at
which time it splits off in four sections to release the thin-shelled nut.
The seeds of the pecan are edible, with a rich, buttery flavor.
They can be eaten fresh or used in cooking, particularly in sweet desserts. One
of the most common desserts with the pecan as a central ingredient is the pecan pie, a
traditional Southern U.S. dish.
Pecans are also a major ingredient in praline candy.
In addition to the pecan seed, the wood is also used in making
furniture and wood flooring as well as flavoring fuel for smoking meats.
Cultivation
Pecans were one of the most recently domesticated major crops. Although wild pecans were
well known among the colonial Americans as a delicacy, the commercial growing
of pecans in the United States did not begin until the 1880s.[11]Today,
the U.S. produces between 80% and 95% of the world's pecans, with an annual
crop of 150–200 thousand tons[12] from more than 10 million trees.[13] The nut harvest for growers is typically
around mid-October. Historically, the leading pecan-producing state in the U.S.
has been Georgia, followed by Texas, New
Mexico, Arizona, Louisiana, and Oklahoma, the
largest orchard being Stahmann Farms in south-central New Mexico;[14] pecans are also grown in Alabama, California, Florida, Arkansas, Kansas, Mississippi, Missouri, South
Carolina, North
Carolina, Tennessee, and Hawaii.
Outside the United States, pecans are grown in Argentina, Australia, Brazil, China, Israel, Mexico, Peru, and South
Africa. They can be grown from USDA hardiness
zones approximately
5 to 9, provided summers are also hot and humid.
Pecan trees may live and bear edible seeds for more than 300
years. They are mostly self-incompatible,
because most cultivars are clones derived from wild trees which
show incomplete dichogamy.
Generally, two or more trees of different cultivars must be present to
pollinate each other.
Choosing cultivars can be a complex practice, based on the
Alternate Bearing Index (ABI) and their period of pollinating. Commercial
planters are most concerned with the ABI, which describes a cultivar's
likelihood to bear on an alternating years (index of 1.0 signifies highest
likelihood of bearing little to nothing every other year). The period of pollination groups all
cultivars into two families: those that shed pollen before they can receive
pollen (protandrous), and those that shed pollen after becoming
receptive to pollen (protogynous). Planting cultivars from both families
within 250 feet is recommended for proper pollination.
Breeding and selection programs
Active breeding and selection programs are carried out by the
USDA Agricultural Research Service with growing locations at Brownwood and College Station, Texas.[17]While
selection work has been done since the late 1800s, most acreage of pecans grown
today is of older cultivars, such as 'Stuart', 'Schley', and 'Desirable', with
known flaws but also with known production potential. Newer cultivars, such as 'Elliot', are
increasing in popularity due to their resistance to certain regional
climate-related diseases.[18] The long cycle time for pecan trees plus
financial considerations dictate that new varieties go through an extensive
vetting process before being widely planted. Numerous examples of varieties
produce well in Texas, but fail in the Southeastern U.S. due to increased disease
pressure. Selection programs are ongoing at the state level, with Alabama,
Arkansas, Georgia, Kansas, Florida, Missouri, and others having trial
plantings.
Varieties adapted from the southern tier of states north through
some parts of Iowa and even into southern Canada are available from nurseries.
Production potential drops significantly when planted further north than
Tennessee. Most breeding efforts for northern-adapted varieties have not been
on a large enough scale to significantly affect production. Varieties that are
available and adapted (e.g., 'Major', 'Martzahn', 'Witte', 'Greenriver', and
'Posey') in zones 6 and farther north are almost entirely
selections from wild stands. A northern-adapted variety must be grafted onto a
northern rootstock to avoid freeze damage.
The pecan is a 32-chromosome species, and can hybridize with
other 32-chromosome members of the Carya genus, such
as Carya ovata, Carya laciniosa, and Carya cordiformis. Most such hybrids are
unproductive, though a few second-generation hybrids have potential for
producing hickory-flavored nuts with pecan nut structure. Such hybrids are
referred to as "hicans" to indicate their hybrid origin.
Diseases
In the Southeastern United States, nickel deficiency in C. illinoinensis produces a disorder called mouse-ear
in trees fertilized with urea. Similarly,
zinc deficiency causes rosetting of the leaves.
Pecans are also prone to infection by fungi, especially in humid
conditions. Ziram is a common fungicide used to prevent
scab and anthracnose in pecans.
Nutrition
In 100 g, pecans provide 691 Calories and over 100% of the Daily
Value (DV)
for total fat.
Pecans are a rich source of dietary
fiber (38%
DV), manganese (214% DV), magnesium (34% DV), phosphorus (40% DV), zinc (48% DV) and thiamin (57% DV).[20] Pecans are also a good source (10-19% DV)
of protein, iron, and B vitamins. Their
fat content consists mainly of monounsaturated fatty acids, mainly oleic
acid (57% of
total fat), and the polyunsaturated fatty acid linoleic acid (30%
of total fat).
Evolutionary development
The pecan, Carya
illinoinensis, is a member of the Juglandaceae family.
Juglandaceae are represented worldwide by between seven and 10 extant genera
and more than 60 species. Most of these species are concentrated in the
Northern Hemisphere of the New World, but can be found on every continent
except for Antarctica. The first fossil examples of the family appear during
the Cretaceous.
Differentiation between the subfamilies of Engelhardioideae and Juglandioideae
occurred during the early Paleogene, about 64 million years ago. Extant
examples of Engelharioideae are generally tropical and evergreen, while those
of Juglandioideae are deciduous and found in more temperate zones. The second
major step in the development of the pecan was a change from wind-dispersed
fruits to animal dispersion. This dispersal strategy coincides with the
development of a husk around the fruit and a drastic change in the relative
concentrations of fatty acids. The ratio of oleic to linoleic acids are
inverted between wind- and animal-dispersed seeds.Further differentiation from
other species of Juglandaceae occurred about 44 million years ago during the Eocene. The fruits
of the pecan genus Carya differ from those of the walnut genus Juglans only in the formation of the husk of
the fruit. The husks of walnuts develop from the bracts, bracteoles, and
sepals, or sepals only. The husks of pecans develop from the bracts and the
bracteoles only.
History
Before European settlement, pecans were widely consumed and
traded by Native Americans. As a food source, pecans are a natural choice for
preagricultural society. They can provide two to five times more energy per
unit weight than wild game, and require no preparation. As a wild forage, the
fruit of the previous growing season is commonly still edible when found on the
ground. Hollow tree trunks, found in abundance in pecan stands, offer ideal
storage of pecans by humans and squirrels, alike.
Pecans first became known to Europeans in the 16th century. The
first Europeans to come into contact with pecans were Spanish explorers in what
is now Mexico, Texas, and Louisiana. These Spanish explorers called the pecan, nuez de la arruga, which
roughly translates to "wrinkle nut". They were called this for their
resemblance to wrinkles. The genus Carya does not exist in the Old World.
Because of their familiarity with the genus Juglans, these early explorers referred to the
nuts as nogales and nueces,
the Spanish terms for "walnut trees" and "fruit of the
walnut". They noted the particularly thin shell and acorn-like shape of
the fruit, indicating they were indeed referring to pecans. The Spaniards took the pecan into Europe, Asia, and Africa beginning in the 16th century. In 1792, William
Bartram reported
in his botanical book, Travels,
a nut tree, Juglans exalata that some botanists today argue was
the American pecan tree, but others argue was hickory, Carya ovata. Pecan trees are
native to the United States, and writing about the pecan tree goes back to the
nation's founders. Thomas
Jefferson planted
pecan trees, C. illinoinensis (Illinois nuts), in his nut orchard at
his home, Monticello, in Virginia. George
Washington reported
in his journal that Thomas Jefferson gave him "Illinois nuts",
pecans, which Washington then grew at Mount
Vernon, his Virginia home.
Symbolism
In 1906, Texas Governor James Stephen Hogg asked
that a pecan tree be planted at his grave instead of a traditional headstone,
requesting that the seeds be distributed throughout the state to make Texas a
"Land of Trees". His
wish was carried out and this brought more attention to pecan trees. In 1919,
the 36th Texas Legislature made the pecan tree the state tree of Texas where the town of San Saba claims to be "The Pecan Capital of the
World". Several other
American towns and regions host annual events celebrating the pecan harvest.
PRICE
$27.76/KG OR
$12.62/IB
For more information:
mobile: +2348039721941
contact person: emeaba uche
e-mail: emeabau@yahoo.com
website: www.franchiseminerals.com
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