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Posts tagged “Pith

Black Walnut – Identification in Winter

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Black walnut (Juglans nigra) is a relatively easy tree to identify, as it has so many distinctive qualities. In the summer there are round, tennis-ball-sized nuts, which have a delightful smell.  The bark of black walnut is dark and deeply furrowed.  Best of all are the twigs and buds.  If you cut a twig at an angle, you will see the central portion, or pith, is chambered.  It is also brown.  The only other tree that is chambered (not solid) like this is its relative, butternut (Juglans  cinerea), and butternut’s pith is buff colored.  The buds of black walnut are greyish and fuzzy – lacking bud scales.  By far the most amusing thing about black walnut (and butternut) is its leaf scars – the scar left when a leaf falls off.  The vessels that transport food and water, called vascular bundles, are darker than the rest of the scar, and are shaped in such a way that the leaf scar resembles nothing more than the smiling face of a monkey!  (Butternut leaf scars also look like monkeys, but they have a “furrowed brow” of fuzz on the top edge of the leaf scar.)