Black Walnut

Black Walnut (Juglans nigra /Juglandaceae). Black walnut is native to the eastern United States, from southern Minnesota east to Pennsylvania, New Jersey, New York; south to South Carolina, Georgia, Florida, Alabama; west to Texas; and north through Oklahoma, Kansas, Nebraska, and South Dakota. Black walnut trees reach heights of 120 ft (37 m), with a diameter of over 3 ft (1 m). Juglans nigra sapwood is light tan, with the heartwood being a dark, chocolate brown, sometimes having a purplish cast. Juglans nigra is hard, heavy, hard and stiff (high shock resistance). The wood has a straight grain, is easily worked, finishes well and holds paint and stain. It is a most durable wood, even under conditions favorable to decay (moist conditions). It is used for cabinets, fixtures, furniture, gunstocks, interior paneling, novelties and veneer.

http://ufei.calpoly.edu/urbanwood/woodproperties.lasso#content.

Characteristics found in the American Black Walnut (Juglans nigra):

• Semi-Ring Porous
• Reticulate parenchyma
• Tyloses & deposits
• Simple perforations
• I/V pits large (13 - 50µ)
• Rays 1-8 seriate & homocellular to heterocellular
• Ray cells round as viewed on the tangential surface
• Crystals in Axial Parenchyma (chains of 1-5)
• “Gashes” in Latewood Vessels

WOOD SLIDES
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Cross-section of American Black Walnut (Juglans nigra) showing growth ring boundary and reticulate parenchyma in the latewood.	Radial section of American Black Walnut (Juglans nigra) showing a chain of crystals.	Radial section of American Black Walnut (Juglans nigra) showing “gashes” in a latewood vessel.
Radial section of American Black Walnut (Juglans nigra) showing a close-up of “gashes” in a latewood vessel.	Radial section of American Black Walnut (Juglans nigra) showing inter-vessel pits.	Tangential section of American Black Walnut (Juglans nigra) showing circular ray cells.

CHARCOAL SLIDES