Smart, Cost-Effective, Treasured for Generations.

Black Walnut

Juglans nigra
 
 

Stain Selector

Clear

Light

Medium

Dark

 

The roots of the walnut tree release a toxic material which may kill other plants growing above them. From the time of ancient Greeks until well into modern European history, walnuts symbolized fertility and were strewn at weddings. Just the opposite, in Romania, brides who wished to delay childbearing placed into the bodice of their wedding dresses one walnut for each year they hoped to wait.

Where It Grows

Throughout Eastern U.S., but principal commercial region is the Central states. Average tree height of 100 to 150 feet.

Main uses

Furniture, cabinets, architectural millwork, doors, flooring, paneling, and gun stocks. A favored wood for using in contrast with lighter-colored species.

Relative Abundance

1.9 percent of total U.S. hardwoods commercially available.

Did You Know?

Walnut is one of the few American species planted as well as naturally regenerated.

General Description

The sapwood of walnut is creamy white, while the heartwood is light brown to dark chocolate brown, occasionally with a purplish cast and darker streaks. The wood develops a rich patina that grows more lustrous with age. Walnut is usually supplied steamed, to darken sapwood. The wood is generally straight-grained, but sometimes with wavy or curly grain that produces an attractive and decorative figure. This species produces a greater variety of figure types than any other.

Working Properties

Walnut works easily with hand and machine tools, and nails, screws and glues well. It holds paint and stain very well for an exceptional finish and is readily polished. It dries slowly, and care is needed to avoid kiln degrade. Walnut has good dimensional stability.

Physical Properties

Walnut is a tough hardwood of medium density, with moderate bending and crushing strengths and low stiffness. It has a good steam-bending classification.

Availability

Reasonable availability with regional limitations.

Working Properties


Machining

 
 
 
 
 
Poor
Good

Nailing

 
 
 
 
 
Poor
Good

Screwing

 
 
 
 
 
Poor
Good

Gluing

 
 
 
 
 
Poor
Good

Finishing

 
 
 
 
 
Poor
Good
 

Strength and Mechanical Properties (inch-pound)a


 

Static Bending

Moisture Content

Specific Gravity (b)

Modulus of Rupture
(lbf/in2)

Modulus of Elasticity (c)
(106 lbf/in2)

Work to Maximum Load
(in-lbf/in3)

Green-12% 0.51-0.55 9,500-14,600 1.42-1.68 10.7-14.6

Impact Bending
to Grain
(in)

Compression
Parallel to Grain
(lbf/in2)

Compression
Perpendicular to Grain
(lbf/in2)

Shear
Parallel to Grain
(lbf/in2)

Tension
Perpendicular to Grain
(lbf/in2)

Side Hardness
(lbf)

34-37 4,300-7,580 490-1,010 1,220-1,370 570-690 900-1,010

a) Results of tests on small clear specimens in the green and air-dried conditions. Definition of properties; impact bending is height of drop that causes complete failure, using 0.71-kg (50 lb.) hammer; compression parallel to grain is also called maximum crushing strength; compression perpendicular to grain is fiber stress at proportional limit; shear is maximum shearing strength; tension is maximum tensile strength; and side hardness is hardness measured when load is perpendicular to grain.

b) Specific gravity is based on weight when ovendry and volume when green or at 12% moisture content

c) Modulus of elasticity measured from a simply supported, center-loaded beam, on a span depth ratio of 14/1. To correct for shear reflection, the modulus can be increased by 10%.