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Juglans nigra

Juglans nigra L.

Wallia nigra (L.) Alef.

Eastern Black Walnut, Black Walnut

KingdomPlantaePlants, but not fungi, lichens, or algae
SubkingdomTracheobiontaVascular plants—plants with a “circulatory system” for delivering water and nutrients
DivisionMagnoliophytaFlowering plants, also known as angiosperms
ClassMagnoliopsidaDicotyledons—plants with two initial seed leaves
SubclassRosidaeRoses, legumes, proteas, dogwoods, hydrangeas, mistletoes, euphorbias, grapes, many more
OrderFagalesBirch, she-oak, beech, walnut, bayberry, others
FamilyJuglandaceaeWalnut family
GenusJuglansClassical Latin name for walnut, possibly from Jovis, “of Jupiter or Jove,” and glans, an acorn or nut
SpeciesnigraLatin for “black”

About plant names...

Eastern black walnut is a North American native, the only walnut family tree that is a native. It is a member of the hickory family. The genus Juglans means roughly “a nut fit for a god.” This variety of walnut is prized by furniture makers, but increasingly scarce.

Plants: Trees reach 98-131' (30-40 m). In the forest, the trunk is tall and mostly free of branches; in the open, the trunk is short and the crown is larger. Furrowed bark is gray-black.

Leaves: 12-24" (30-60 cm) long, composed of 15-23 leaflets, each 2½-4" (7-10 cm) × ¾-1" (2-3 cm).

Flowers: Male flowers are hanging catkins (long, drooping flowers) 3-4" (8-10 cm) long. Female flowers form on branch tips in groups of 2-5, becoming green fruits almost the size of tennis balls.

Fruits: The green fruits have a somewhat bumpy surface, like the surface of a basketball. They dry to dark brown lightweight balls. The shipping industry could learn a lot from these seed pods. The outer quarter inch dries to a nice protective form-fitted styrofoam layer with a hard shell, and the pod steadfastly refused all careful attempts to open it, yielding only to the force of several hammer blows. The shells are so hard, they are used commercially for abrasive cleaners.

Historically, walnut shells were used to make ink. The brown color comes from juglone (5-hydroxy-alpha-napthaquinone), and also from tannins that turn black on contact with iron. You can make your own ink, but be forewarned that the black ink is very difficult to remove from the skin.

Online References:

Juglans nigra on Carolina Nature, from Will Cook

Juglans nigra on Missouriplants.com

Juglans nigra on Wikipedia

Juglans nigra at the USDA Forest Service's Silvics of North America site

Juglans nigra at Illinois Wildflowers

Juglans nigra on Plants for a Future, a resource and information centre for edible and otherwise useful plants

Juglans nigra at the Lady Bird Johnson Wildflower Center

Juglans nigra at the University of Connecticut Plant Database

Juglans nigra at the Virginia Tech Department of Forest Resources and Environmental Conservation

Juglans nigra at the Vanderbilt University Bioimages web site

Juglans nigra on the USDA Forest Service's Fire Effects Information Database

Juglans nigra on CalPhotos

References:

Sibley, David Allen, The Sibley Guide to Trees, Alfred A. Knopf, 2009, p. 137

Juglans nigra (Eastern Black Walnut, Black Walnut)

8/14/2017 · Beaver Brook Conservation Area, Old Long Loop, Hollis, NH
≈ 6 × 4" (16 × 11 cm)

Juglans nigra (Eastern Black Walnut, Black Walnut)

10/2/2013 · Beaver Brook Assn Conservation Lands, Chestnut Farm, Hollis, NH
≈ 10 × 7" (25 × 16 cm)

Juglans nigra (Eastern Black Walnut, Black Walnut)

10/4/2010 · Susan and Raimond’s, Phoenix, MD
≈ 14 × 21" (34 × 52 cm)

Juglans nigra (Eastern Black Walnut, Black Walnut)

10/4/2010 · Susan and Raimond’s, Phoenix, MD
≈ 8 × 6" (21 × 15 cm)

Juglans nigra (Eastern Black Walnut, Black Walnut)

8/18/2012 · Nashua River Rail Trail, Groton Center, Groton, MA

Juglans nigra (Eastern Black Walnut, Black Walnut)

10/2/2013 · Beaver Brook Assn Conservation Lands, Chestnut Farm, Hollis, NH
≈ 12 × 8" (31 × 21 cm)

Juglans nigra (Eastern Black Walnut, Black Walnut)

7/3/2012 · By Jacquelyn Boyt

Juglans nigra description by Thomas H. Kent, last updated 14 Aug 2017.

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Juglans nigra (Eastern Black Walnut, Black Walnut)

12/4/2010
≈ 4 × 3" (10 × 7.4 cm)

Juglans nigra (Eastern Black Walnut, Black Walnut)

12/4/2010
≈ 4 × 3½" (11 × 8.7 cm)

Juglans nigra (Eastern Black Walnut, Black Walnut)

7/3/2012 · By Jacquelyn Boyt

Juglans nigra (Eastern Black Walnut, Black Walnut)

10/2/2013 · Beaver Brook Assn Conservation Lands, Chestnut Farm, Hollis, NH

Juglans nigra (Eastern Black Walnut, Black Walnut)

10/2/2010 · Route 209, Milford, PA
≈ 11 × 7" (27 × 18 cm) ID is uncertain

Juglans nigra (Eastern Black Walnut, Black Walnut)

8/14/2017 · Beaver Brook Conservation Area, Old Long Loop, Hollis, NH
≈ 8 × 5" (20 × 13 cm)

Juglans nigra (Eastern Black Walnut, Black Walnut)

10/9/2010
≈ 7 × 4½" (17 × 11 cm)

Juglans nigra (Eastern Black Walnut, Black Walnut)

10/4/2010 · Susan and Raimond’s, Phoenix, MD
≈ 4 × 4" (10 × 10 cm)

Juglans nigra (Eastern Black Walnut, Black Walnut)

10/10/2011 · Near Nashua River, Groton, MA

Juglans nigra (Eastern Black Walnut, Black Walnut)

10/2/2013 · Beaver Brook Assn Conservation Lands, Chestnut Farm, Hollis, NH
≈ 12 × 8" (31 × 21 cm)

Juglans nigra (Eastern Black Walnut, Black Walnut)

8/18/2012 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 4½ × 3½" (11 × 9.6 cm)

Range: Zones 4-9:

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