Black Walnut Tree Information

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Black Walnut Tree Information

The black walnut tree, or Juglan nigra, is commonly found through the central and eastern parts of North America. Approximately 21 species exist around the globe, including in Europe and Japan and as far south as Argentina.

The black walnut is one of nearly half-a-dozen walnut species that are native in North America. When growing in wild areas, black walnuts are found in riparian zones, which are those areas lying between creeks or rivers and denser woodland. Classified as shade intolerant, the black walnut prefers a full-sun location.

Black walnuts are deciduous and grow to between 30 and 130 feet tall. They may be identified by their pinnate leaves, each of which contains between five and 25 leaflets. Each leaflet is serrated. Another defining characteristic of the black walnut is the hard-shelled fruit, which has a rounded shape.

When the black walnut is dormant, it's most easily identified by its dark, furrowed bark. Leaf scars may be found along the twigs, and these are shaped like upside-down shamrocks.