Carya illinoinensis

Pecan

a perennial woody deciduous member of the Carya genus in the family Juglandaceae.

No photo available

Taxonomy and growth

Genus
Carya
Life cycle
perennial
Foliage
deciduous
Woodiness
woody
Growth rate
moderate
Height
50 m
Fertility
Self fertile, Wind
Flower type
monoecious
Pollinators
Wind

Uses

Toxicity

Toxicity warning. The historical record reports a hazard for this plant. Do not use it to decide which parts are safe to eat or use medicinally.

None known

Edible uses

Seed - raw or cooked[12][15]. Sweet and delicious, they make an excellent dessert and are also often added to ice cream, used in cakes, bread etc[3][5]. A milk can be made from the seed and is used to thicken soups, season corn cakes, hominy etc[5]. The seed is up to 4cm long and is produced in clusters of 3 -11[15][8]. The seed ripens in late autumn and, when stored in its shell in a cool place, will keep for at least 6 months[K]. An edible oil is obtained from the seed[4][5]. The leaves are said to be used as a tea[4][5].

Product or use
Milk
Product or use
Oil
Product or use
Tea
Plant part
Seed

Medicinal uses

Historical medicinal uses. These records describe reported uses. They do not establish safety or effectiveness. Ask a qualified health professional before using any plant medicinally.

The bark and leaves are astringent[7]. A decoction of the bark has been used to treat TB[10]. The pulverized leaves have been rubbed on the skin to treat ringworm[10].

Product or use
Astringent
Product or use
Parasiticide
Product or use
TB

Material uses

Wood - coarse-grained, hard, heavy, brittle, not strong. It weighs 45 lb. per cubic foot. It is not as valuable a timber as other members of this genus and is used mainly for fuel and occasionally to make wagons and agricultural implements[12][15][7][9].

Product or use
Fuel
Product or use
Wood

Ecology and functions

Ecosystem niche
Canopy

Environment

Range
Southern N. America - mainly along the Mississippi river valley.
Habitat
Rich moist soils of bottomlands[8], especially along the sides of streams[9].
Light
full sun
Shade tolerance
no shade
Water
moderate
Hardiness
Zone 5+
Soil textures
sandy, loamy, clay
Soil pH
very acid, acid, neutral, alkaline, very alkaline
Tolerates Nutritionally Poor Soil
No
Drought
intolerant

Propagation

Seed - requires a period of cold stratification. It is best sown in a cold frame as soon as it is ripe[14]. Stored seed should be kept moist (but not wet) prior to sowing and should be sown in a cold frame as soon as possible[14]. Where possible, sow 1 or 2 seeds only in each deep pot and thin to the best seedling. If you need to transplant the seedlings, then do this as soon as they are large enough to handle, once more using deep pots to accommodate the tap root. Put the plants into their permanent positions as soon as possible, preferably in their first summer, and give them some protection from the cold for at least the first winter[78, K]. Seed can also be sown in situ so long as protection is given from mice etc and the seed is given some protection from cold[6] (a plastic bottle with the top and bottom removed and a wire mesh top fitted to keep the mice out is ideal)

Cultivation

Prefers a deep moisture-retentive loam in a sunny sheltered position, requiring a good summer for best development[1][13][2][6]. Tolerates a pH in the range 4.5 to 8.3. Trees are fairly fast growing[6]. Trees do not grow very well in Britain, requiring hotter summers than are normally experienced here in order to fruit and fully ripen their wood[6]. However, a tree at Cambridge botanical gardens was 20 metres tall in 1985. Trees are said to be hardy to about -12°c, the same report also says that they are hardy to zone 5[6], which would experience considerably lower temperatures than this. Trees are probably much hardier when grown in areas with hot summers. In the wild, trees grow best in areas where summer temperatures average 24 - 30°c and the humidity is high[8]. Often cultivated for its edible seed, there are some named varieties[5]. Trees come into bearing when about 20 years old, the best period of production being between the ages of 75 to 225 years old[8]. Mature trees regularly give yields of 225 kilos, whilst yields of 450 kilos have been recorded[8]. A number of cultivars have been developed in N. America that succeed quite far north in that country[6]. These cultivars include:- 'Carlson 3'. Early maturing, it is being trialled in Canada[5]. 'Devore'. An early fruiting form with small nuts that have an excellent flavour[5]. 'Gibson'. Precocious, protandrous, the nuts are of medium size with a good flavour[5]. 'Green Island'. Amongst the hardiest of cultivars, it has been selected for nut size, flavour and productivity[5]. 'Mullahy'. Hardy, precocious and very productive, it has ripened in Ontario[5]. Nuts are fairly large with an excellent flavour. 'Voiles 2'. Usually ripens as far north as Ontario and New York[5]. The wind-blown pollen is a significant cause of hay fever in the Unitd States[11]. This species is the State Tree of Texas[11]. Plants are strongly tap-rooted and should be planted in their permanent positions as soon as possible[1][2]. Sowing in situ would be the best method so long as the seed could be protected from mice[1][6]. Trees are late coming into leaf (usually late May to June) and lose their leaves early in the autumn (usually in October)[2]. During this time they cast a heavy shade. These factors combine to make the trees eminently suitable for a mixed woodland planting with shrubs and other trees beneath them[2]. Plants in this genus are notably resistant to honey fungus[6]. Most species in this genus have quite a wide range of distribution and, in order to find trees more suited to this country, seed from the most appropriate provenances should be sought[2]. Most trees growing in Britain at present tend to only produce good seed after hot summers[2]. Trees are self-fertile but larger crops of better quality seeds are produced if cross-pollination takes place[8].

References

  1. F. Chittendon. RHS Dictionary of Plants plus Supplement. 1956 Oxford University Press 1951-00-00

  2. ? The Plantsman. Vol. 9. 1986 - 1987. Royal Horticultural Society 1986-00-00

  3. Vines. R. A. Trees of Central Texas. University of Texas Press 1987-00-00 ISBN 0-292-78958-3

  4. Kunkel. G. Plants for Human Consumption. Koeltz Scientific Books 1984-00-00 ISBN 3874292169

  5. Facciola. S. Cornucopia - A Source Book of Edible Plants. Kampong Publications 1990-00-00 ISBN 0-9628087-0-9

  6. Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press 1992-00-00 ISBN 0-333-47494-5

  7. Vines. R.A. Trees of North Texas University of Texas Press. 1982-00-00 ISBN 0292780206

  8. Elias. T. The Complete Trees of N. America. Field Guide and Natural History. Van Nostrand Reinhold Co. 1980-00-00 ISBN 0442238622

  9. Britton. N. L. Brown. A. An Illustrated Flora of the Northern United States and Canada Dover Publications. New York. 1970-00-00 ISBN 0-486-22642-5

  10. Moerman. D. Native American Ethnobotany Timber Press. Oregon. 1998-00-00 ISBN 0-88192-453-9

  11. Diggs, Jnr. G.M.; Lipscomb. B. L. & O'Kennon. R. J Illustrated Flora of North Central Texas Botanical Research Institute, Texas. 1999-00-00 http://artemis.austincollege.edu/acad/bio/gdiggs/NCTXpdf.htm

  12. Uphof. J. C. Th. Dictionary of Economic Plants. Weinheim 1959-00-00

  13. Howes. F. N. Nuts. Faber 1948-00-00

  14. Sheat. W. G. Propagation of Trees, Shrubs and Conifers. MacMillan and Co 1948-00-00

  15. Sargent. C. S. Manual of the Trees of N. America. Dover Publications Inc. New York. 1965-00-00 ISBN 0-486-20278-X

Edit this page