Carya spp.
Family: Juglandaceae
Hickory

Hickory (Carya spp.) is composed of at least 16 species native to Asia [4], Central America [4] and North America [1]). The word carya is from the Greek name for nut. This group can be split into the true hickories and the pecans based on microanatomy.

True Hickory Group (earlywood without parenchyma bands):

Carya glabra–bitternut, black hickory, broom hickory, brown hickory, coast pignut hickory, false shagbark, hard shell, little pignut, little shagbark, nutmeg hickory, oval pignut hickory, pignut, pignut hickory, red hickory, redheart hickory, small fruited hickory, small pignut, smoothbark hickory, swamp hickory, sweet hickory, sweet pignut, sweet pignut hickory, switch-bud hickory, true hickory, white hickory.

Carya lacinosa–big shagbark, big shagbark hickory, big shellbark, big shellbark hickory, bigleaf shagbark hickory, bottom shellbark, king nut, ridge hickory, shellbark hickory, thickbark hickory, thick shellbark, thick shellbark hickory, true hickory, western shellbark.

Carya ovata–bird’s eye hickory, Carolina hickory, curly hickory, littlenut shagbark hickory, little pignut, little shagbark, mockernut hickory, red hickory, redheart hickory, scalybark hickory, shagbark, shagbark hickory, shagbark walnut, shellbark, shellbark hickory, shellbark tree, skid hickory, small pignut, small pignut hickory, southern hickory, southern shagbark hickory, southern shellbark, sweet walnut,true hickory, upland hickory, white hickory, whiteheart hickory, white walnut.

Carya tomentosa –big-bud, big hickory, black hickory, bullnut, common hickory, hardbark hickory, hickory-nut, hognut, mockernut, mockernut hickory, red hickory, true hickory, white hickory, whiteheart hickory

Pecan Hickory Group (earlywood with parenchyma bands):

Carya aquatica–bitter pecan, bitter water hickory, faux hickory, lowground hickory, lowland hickory, noot hickory, not hickory, pecan, pecan hickory, pignut hickory, swamp hickory, water bitternut, water hickory, wild pecan.

Carya cordiformis–bitter hickory, bitternut, bitternut hickory, bitter pecan tree, bitter pignut, butternut, butternut hickory, highland hickory, pig hickory, pignut,pignut hickory, pig walnut, redheart hickory,swamp hickory, white hickory, yellow bud hickory.

Carya floridana–Florida hickory, scrub hickory.

Carya illinoensis–faux hickory, pecan, pecan hickory, pecan nut, pecan tree, sweet pecan.

Carya myristicaeformis –bitter water hickory, bitter waternut, blasted pecan, nutmeg hickory, scalybark hickory, shagbark, shagbark hickory, shellbark hickory, swamp hickory, upland hickory.

Carya pallida –pale hickory, paleleaf hickory, pallid hickory, pignut hickory, sand hickory.

Carya texana –black hickory, buckley hickory, pignut hickory, Texas hickory.

Distribution

Eastern to Midwestern United States.

The Tree

Hickory trees can reach a height of 140 ft (43 m), with a diameter of 4 ft (1.2 m).

The Wood

General

The sapwood of hickory is white, tinged with brown, while the heartwood is pale to reddish brown. The wood is known for its strength and shock resistance. It is difficult to dry or season. It rates above average in most working properties, except in shaping and nail-holding ability. The wood of pecans is rated slightly below that of true hickories.

Mechanical Properties (2-inch standard)

				Compression
	Specific gravity	MOE 10^6 lbf/in^2	MOR 10^3 lbf/in^2	Parallel 10^3 lbf/in^2	Perpendicular 10^3 lbf/in^2	WML^a in-lbf/in^3	Hardness lbf	Shear 10^3 lbf/in^2
True Hickory Group Carya glabra (pignut hickory)
Green	0.66	1.65	11.7	4.81	0.92	31.7	--	1.37
Dry	--	2.26	20.1	9.19	1.98	30.4	--	2.15
Carya lacinosa (shellbark hickory)
Green	0.62	1.34	10.5	3.92	0.81	29.9	--	1.19
Dry	--	1.89	18.1	8.00	1.80	23.6	--	2.11
Carya ovata (shagbark hickory)
Green	0.64	1.57	11.0	4.58	0.84	23.7	--	1.52
Dry	--	2.16	20.2	9.21	1.76	25.8	--	2.16
Carya tomentosa (mockernut hickory)
Green	0.64	1.57	11.1	4.48	0.81	26.1	1.28	0.92
Dry	--	2.22	19.2	8.94	1.73	22.6	1.74	1.40
^aWML = Work to maximum load. ^bReference (98). ^cReference (59).

				Compression
	Specific gravity	MOE 10^6 lbf/in^2	MOR 10^3 lbf/in^2	Parallel 10^3 lbf/in^2	Perpendicular 10^3 lbf/in^2	WML^a in-lbf/in^3	Hardness lbf	Shear 10^3 lbf/in^2
Pecan Hickory Group Carya aquatica (water hickory)
Green	0.61	1.56	10.7	4.66	0.88	18.8	--	1.44
Dry	--	2.02	17.8	8.60	1.55	19.3	--	--
Carya cordiformis (biternut hickory)
Green	0.60	1.40	10.3	4.57	0.80	20.0	--	1.24
Dry	--	1.79	17.1	9.04	1.68	18.2	--	--
Carya illinoensis (pecan)
Green	.60	1.37	9.8	3.99	0.78	14.6	1310	1.48
Dry	--	1.73	13.7	7.85	1.72	13.8	1820	2.08
Carya myristicaeformis (nutmeg hickory)
Green	.0.56	1.29	9.10	3.98	0.76	22.8	--	1.03
Dry	.0.69	1.70	16.6	6.91	1.57	25.1	--	--
^aWML = Work to maximum load. ^bReference (98). ^cReference (59).

Drying and Shrinkage

Type of shrinkage	Percentage of shrinkage (green to final moisture content)
	0% MC	6% MC	20% MC
True Hickory Group Carya glabra (pignut hickory)
Tangential	11.5	9.2	3.8
Radial	7.2	5.8	2.4
Volumetric	17.9	14.3	6.0
Carya lacinosa (shellbark hickory)
Tangential	12.6	10.1	4.2
Radial	7.6	6.1	2.5
Volumetric	19.2	15.4	6.4
Carya ovata (shagbark hickory)
Tangential	10.5	8.0	3.3
Radial	7.0	5.6	2.3
Volumetric	16.7	13.4	5.6
Carya tomentosa (mockernut hickory)
Tangential	11.0	8.8	3.7
Radial	7.7	6.2	2.6
Volumetric	17.8	14.3	6.0
^aBirch shrinks considerably during drying. References: 0% MC (98), 6% and 20% MC (90).

Type of shrinkage	Percentage of shrinkage (green to final moisture content)
	0% MC	6% MC	20% MC
Pecan Hickory Group Carya aquatica (water hickory)
Tangential	--	--	--
Radial	--	--	--
Volumetric	13.6	--	--
Carya cordiformis (bitternut hickory)
Tangential	--	—	—
Radial	--	—	—
Volumetric	13.6	—	—
Carya illinoensis (pecan)
Tangential	8.9	—	—
Radial	4.9	—	—
Volumetric	13.6	—	—
Carya myristicaeformis (nutmeg hickory)
Tangential	--	--	--
Radial	--	--	--
Volumetric	--	--	--
^aBirch shrinks considerably during drying. References: 0% MC (98), 6% and 20% MC (90).

Kiln Drying Schedules^a

	Stock
Condition	4/4, 5/4, 6/4	8/4	10/4	12/4	16/4
Standard	T8-D3	T6-D1	--	—	—
^aReferences (6, 86).

Working Properties:
Hickory is considered difficult to machine and glue. It holds nails well, but it tends to split. It is susceptible to bird peck.

Durability:
Rated as slightly or nonresistant to heartwood decay.

Preservation:
Extremely resistant.
.

Uses:
Tool handles, furniture, cabinetry, ladder rungs, dowels, sportinggoods (including baseball bats, skis and archery equipment), flooring, veneer, plywood, fuelwood, charcoal.

Toxicity:
No information available at this time.

Additional Reading and References Cited (in parentheses)

18, 29, 55, 68, 71, 74, 91.

6. Boone, R.S.; Kozlik,
C.J.; Bois, P.J.; Wengert,
E.M. 1988. Dry kiln
schedules for commercial
woods-temperate and
tropical. Gen. Tech. Rep.
FPL-GTR-57. Madison,
WI: U.S. Department of
Agriculture, Forest Service,
Forest Products Laboratory.

18. Clark, A. 1973. Pecan,
an American wood.
FS-249. Washington, DC:
U.S. Department of
Agriculture, Forest Service.

29. Elias, T.S. 1980. The
complete trees of North
America, field guide and
natural history. New York:
van Nostrand Reinhold
Company.

55. Little, Jr., E.L. 1979.
Checklist of United States
trees (native and
naturalized). Agric. Handb.
541. Washington, DC: U.S.
Department of Agriculture,
Forest Service. U.S.
Government Printing Office.

59. Markwardt, L.J.;
Wilson, T.R.C. 1935.
Strength and related
properties of woods grown
in the United States. Tech.
Bull. 479. Washington,
DC: U.S. Department of
Agriculture, Forest Service.
U.S. Government Printing
Office.

68. Panshin, A.J.; de
Zeeuw, C. 1980. Textbook
of wood technology, 4th ed.
New York: McGraw—Hill
Book Co..

71. Philips, D.R. 1973.
Hickory, an American
wood. FS—241.
Washington, DC: U.S.
Department of Agriculture,
Forest Service.

74. Record, S.J.; Hess
R.W. 1943. Timbers of the
new world. New Haven,
CT: Yale University Press.

86. Simpson, W.T. 1991.
Dry kiln operator's manual.
Ag. Handb. 188. Madison,
WI: U.S. Department of
Agriculture, Forest Service,
Forest Products Laboratory.

90. Summitt, R.; Sliker, A.
1980. CRC handbook of
materials science. Boca
Raton, FL: CRC Press, Inc.
Vol. 4.

91. Taras, M.A.; Kukachka,
B.F. 1970. Separating pecan
and hickory lumber. Forest
Products Journal. 20(4):
58—59.

98. U.S. Department of
Agriculture. 1987. Wood
handbook: wood as an
engineering material. Agric.
Handb. 72. (Rev.)
Washington, DC: U.S.
Department of Agriculture.
466 p.