Defects

A

B

C

Sapwood

No

No

Yes

Heartwood

Slight

Slight

Yes

Color Streaks or Spots

Slight

Slight

Yes

Color Variation

No

Slight

Slight

Sharp Color Contrasts at Joints

Not allowed

Not allowed

Yes

Matching

Book Matched
Slip Matched
Pleasing Matched

Yes
Specify
--

Specify
Specify
Yes

--
--
--

Min. Nominal Width of Face 
Components

Plain-S
Quarter
Rotary

127 mm
76 mm
127 mm

76 mm
76 mm
102 mm

No limit

Small Conspicuous Burls & Pin Knots-Combined Avg. No.

8 per 1 m2

22 per 1 m2

No limit

Conspicuous Burls-Max. Size

9.5 mm

12.7 mm

No limit

Conspicuous Pin Knots-Avg. No.
Dark Part-Max. Dia.
Knots-Max. Dia.

6 per 1 m2
3.2 mm
6.4 mm

11 per 1 m2
3.2 mm
6.4 mm

No limit

Scattered Sound & Repaired Knots-Combined Avg. No.
Max. Dia.-Sound
Max. Dia.-Repaired
Avg. No.-Repaired

No

4 per 3 m2

9.5 mm
3.2 mm
4 per 3 m2

3 per 1 m2

12.7 mm
12.7 mm
4 per 3 m2

Mineral Streaks

Slight

Yes

Yes

Bark Pockets

Less

Max. no. 6
Max. area
3.2 x 25.4 mm

Max. no. 6
Max. area
6.4 x 50.8 mm

Worm Tracks

No

Slight

Slight

Vine Marks

Occasional

Yes

Yes

Cross Bars

Occasional

Yes

Yes

Rough Cut / Ruptured Grain

No

Slight

Slight

Blended Repaired Tapering
Hairline Splits

Max. no. 2
Max. area 1 x
152 mm

Max. no. 4
Max. area 3.2 x 203 mm

Max. no. 4
Max. area 4.8 x 203 mm

Repairs

Small Blending

Blending

Blending

· Unfilled wormholes, open splits, open joints, open bark pockets, or doze not allowed in above grades.
· Sap allowed in rotary in grades A and B; however, the percentage must be agreed upon between buyer and seller. 
· Outside components will be a different size to allow for edge trim loss and certain types of matching.
· For Black Walnut, conspicuous pin knots means sound knots 6.4 mm or less in diameter with dark centers larger than 1.6 mm. Blending pin knots 6.4 mm or less in diameter with dark centers of 1.6 mm or less are allowed in all grades of Black Walnut.