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Black Walnut

Juglans Nigra

INDEX

flora

Species Description

Black Walnut is a perennial, deciduous, stone fruit tree native to Eastern North America. It reaches maturity at 50-100 ft tall. Black walnut produces a compound called Juglone that will inhibit the growth of the majority plants around it. Juglone is released from every part of the tree, although the roots, nuts, and the seeds are the most toxic. The trees are monoecious, so each individual tree contains both male and female flowers. Male flowers are catkins, small scaley, cone-like buds; female flowers are up to 8-flowered spikes. Black Walnut is self fertile, but puts on a better fruit set with two trees. It is generally easy to grow with little attention needed. The tree has numerous uses, such as: nutritional, medicinal, dye, structural/decorative, antibacterial, and herbicidal. Walnut shells are often used as an abrasive in sand blasting or other circumstances where a medium hardness grit is required. The hard black walnut shell is also used commercially in abrasive cleaning, a filtering agent in scrubbers in smoke stacks, cleaning jet engines, cosmetics, and oil well drilling Black walnuts are edible. The drupes (walnuts) are harvested in the fall, dehulled and dried to allow the nut meat to cure for consumption.

Species Details

FAMILY

Juglandaceae

GENUS

Juglandaceae

SIZE

50-100ft

LIFE SPAN

Perennial

HEMISPHERE

Northern

ECOSYSTEM

Forest

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Sources

Philadelphia Orchard Project - Plant Spotlight: Black Walnut (Juglans Nigra)
https://www.phillyorchards.org/2018/10/17/plant-spotlight-black-walnut/

Philly Tree Map - Black Walnut
https://treekey.phillytreemap.org/species/98.html

Wikipedia - Juglans nigra
https://en.wikipedia.org/wiki/Juglans_nigra

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