The walnut tree grows in a sheltered hollow in Mount Airy Arboretum, Cincinnati where it thrives in rich, moist bottomland soil.
Black walnut is a large deciduous tree reaching heights of 70-100 ft (21-30 m) or more. This is a vigorous, spreading tree which can develop a trunk 2-4 ft (0.6-1.2 m) in diameter, and a crown spread of 70 ft (21 m). In forest stands, black walnut usually has a long, clear bole and a small, open crown. When grown out in the open, however, it has a short trunk and a massive spreading crown. Black walnut has large, aromatic, compound leaves, 1-2 ft (30-60 cm) long. It bears rather large oval corrugated nuts that are encased in a thick, fleshy yellow-green hull.
Location Juglans nigra is native to North America, from Massachusetts and southern Ontario to Nebraska, south to Texas, and east to Georgia. It grows best on deep, moist and fertile soils, such as occur along river bottoms.
These ripe walnuts are enjoying their last days hanging around in the warm October sun long after the leaves have fallen.
Culture Light: Black walnut is intolerant of shade. Plant in full sun. Moisture: It likes a moist, well drained soil. Hardiness: USDA Zones 4-9. Propagation: Seeds should be planted in a seed bed as soon as ripe. Named cultivars are grafted onto seedlings.
Black walnut has many uses in the forest products trade, and is often
recognized as one of the most valuable of North American hardwoods. It is
commonly used for gun stocks, cabinetry, and the creation of both solid
and veneered furniture. Unfortunately, its extreme value has
contributed to its extirpation in many parts of its range where
it was formerly common. The nuts are oily, sweet and quite edible, used
most commonly for baking and confections. This large, spreading tree
makes an excellent shade and specimen tree throughout its range.
Handling ripe walnuts will stain bare hands brown as Jack discovered (again) after taking this photo. Walnut foliage, husks and nuts all tend make a mess of decks, patios and roofs with a stain that is difficult to remove from most surfaces.
For sheer elegance, a mature, open grown black walnut tree's massive form and long green leaves cannot be surpassed. Its oily nuts possess a distinctive flavor that makes its English relative pale by comparison.
The black walnut tree creates a zone around its roots that is antagonistic to many other plants. It is thought that this is caused by a chemical, juglone, produced by the tree's roots. Actual contact with the roots by other plants is needed for this reaction to occur. It is not harmful to people or other animals. Although the
virtues of its large foliage and edible nuts have been previously extolled, these same leaves and nuts can be a nuisance to clean up in the fall, especially if you do not plan on eating the nuts!