Common Name(s): Shagbark Hickory
Scientific Name: Carya ovata
Distribution: Eastern United States
Tree Size: 65-100 ft (20-30 m) tall, 1-2 ft (.3-.6 m) trunk diameter
Average Dried Weight: 50 lbs/ft3 (800 kg/m3)
Specific Gravity (Basic, 12% MC): .64, .80
Janka Hardness: 1,880 lbf (8,360 N)
Modulus of Rupture: 20,200 lbf/in2 (139.3 MPa)
Elastic Modulus: 2,160,000 lbf/in2 (14.90 GPa)
Crushing Strength: 9,210 lbf/in2 (63.5 MPa)
Shrinkage: Radial: 7.0%, Tangential: 10.5%, Volumetric: 16.7%, T/R Ratio: 1.5
Hickory Solid Wood Flooring Grades
NWFA-NOFMA SELECT HICKORY/PECAN: Shall have the face practically free of all defects, but the natural color
of the wood shall not be considered a defect. The highest standard grade combines a nearly uniform appearance
with exceptional durability.
The following characters are admitted: variations in the natural color of the wood, heartwood and sapwood; an
occasional small knot or bird peck not over 1/4″ (.250”) (6.35mm) in diameter, provided it does not occur on
edges or ends of the piece; dark streaks not over 1/4″ (.250”) (6.35mm) wide and 3″ (76.2 mm) long (or its
equivalent one (1) to every 3’ (914.4 mm) in length); slight checks not over 1/2″ (.500”) (12.7 mm) long, provided
check is boxed within the piece; small burls; slight torn grain or slight intermittent machine burn, or similar
defect which can be readily removed by the ordinary method of sanding the floor after it is laid; slight scant
back. Pieces with one-half (1/2) tongue, full length of the piece. The wood must be free from shake. Bark
streaks shall not be permitted.
NWFA-NOFMA NO. 1 COMMON HICKORY/PECAN: A floor with varying wood characteristics and colors to
include heavy streaks, stained sapwood, sound knots, checks and small splits. All defects must readily fill and be
The following characteristics are admitted: Broken knots up to 1/2″ (.500”) (12.7 mm) in diameter; distinct color
variations (predominantly dark, discolored pieces not allowed); sticker stain/shadow; numerous dark streaks or
black spots; checks to 1/16″ (.0625”) (1.59 mm) in width, not exceeding 3″ (76.2 mm) in length, and running
parallel and well inside the strip edges; small end split 1/16″ (.0625”) (1.59 mm) wide x 1/2″ (.500”) (12.7 mm) in
length showing no movement; bird pecks to 1/2″ (.500”) (12.7 mm) in diameter where bark is sound and as hard
as surrounding wood. Minor imperfections in machining permitted; torn grain (less than 1/16″ (.0625”) (1.59
mm) deep in an area 2” (50.8 mm) wide x 2” (50.8 mm) wide); slightly torn edges; and an occasional dark
machine burn 1/2″ (.500”) (12.7 mm) in width (no more than two (2) per 3’ (914.4 mm) of length). Pieces with
one-quarter (1/4) tongue, full length of the piece.
NWFA-NOFMA NO. 2 COMMON HICKORY/PECAN: Must be of such character as will lay and give a good serviceable floor. The wood must be firm, and may contain defects of every character. This grade is intended to give a “rustic” appearance.
The following defects are not allowed: Knot holes over 3/8″ (.375”) (9.53 mm) in diameter or unsound knots where
the unsound portion is over 1″ (25.4 mm) in diameter (the unsound portion cannot extend through piece); shake, soft rot, splits and open defects which extend through piece or show movement, torn grain more than 1/4″ (.250”)
(6.35mm) deep, edge splinters, and imperfections in manufacture which would materially impair the serviceability of the floor. Knot holes, bird pecks, worm holes, and the like which will readily fill are admitted. Occasional scant thickness (hit or miss) on the back of the flooring board the entire length of the piece admitted, providing there is full bearing across the board at some point within three inches of the ends. A limited number of pieces with no tongue admitted.