Black Walnut - Juglans nigra

Juglans nigra, also known as the American black walnut, is a deciduous tree with a majestic habit, rapid growth, and large size, making it suitable for large gardens and parks. It forms a trunk with dark and deeply furrowed bark, and develops a wide and rounded crown. Its cut foliage is both imposing and decorative, and turns beautiful yellow shades in autumn. This hardy species thrives in sunny, rich, deep, and moist soil. A beautiful tree that can be used to structure a large space.

Juglans nigra is a member of the small Juglandaceae family, which includes about fifty species, including the common walnut. This tree is native to the eastern and central United States, hence its common name American walnut. It thrives in alluvial, fertile, and deep soils in regions with hot summers, while also being resistant to extreme cold down to -35°C (-31°F) (it is even cultivated in Quebec!). It is a tree known for the beauty of its wood, which is used to make luxury furniture. Highly resistant to moisture, it is particularly ornamental due to its irregular dark brown veins, highly sought after by cabinetmakers for veneering. Its edible nuts are also used by the agri-food industry to extract oil, or to make muffins or candies.
With its rapid growth, this American black walnut can reach a height of 30m (98ft) or more, with a spread of up to 24m (79ft). It forms a single trunk, with dark bark that is the origin of its species name 'nigra'. The bark is densely fissured, forming interlacing relief veins, which give it a certain ornamental aspect. This massive trunk supports an ovoid crown, with an irregular to rounded top, formed by large ramified branches.
The foliage is also decorative, consisting of odd-pinnate leaves (with an odd number of leaflets). With a beautiful dark green colour, the leaves are composed of 13 to 23 leaflets, measuring 30 to 60 cm (12 to 24in) in length, and are alternately inserted on the branches. The upper surface is glabrous and slightly shiny, while the lower surface is covered with a cottony down. In autumn, they turn yellow, creating a beautiful scene in the garden.
However, the flowering is relatively insignificant. The male and female flowers open in late May or early June, with the males appearing as yellowish aments measuring 5 to 10 cm (2 to 4in) in length, but too small in comparison to the tree's mass to be truly decorative. After fertilisation, the female flowers turn into fruits that ripen in October. Spherical in shape, they measure 4 to 5 cm (2in) in diameter, with a very hard shell surrounded by a green husk that later turns black, and is loved by squirrels. Although edible, the nuts have a lower taste value compared to those of the common walnut.

This American walnut will thrive in a very large property, allowing it to be planted as a specimen tree on a lawn, alongside other large specimens. Plant a Paulownia tomentosa in front of it, a beautiful fast-growing tree that has similar requirements. Its large flower-shaped leaves will contrast well with the delicacy of your American walnut's foliage, and the imposing vegetation of the latter will provide a green background to admire the purple flowering of Paulownia, which is more difficult to discern against the sky. For a contrast of colours, opt for the Gleditsia triacanthos Sunburst, a thornless honey locust with golden yellow foliage in spring that turns orange-yellow in autumn.  To complete the picture, nothing beats Quercus rubra, an American red oak that can rival Juglans nigra in size, and whose incredible vermilion red autumn attire will respond to the yellow livery of the walnut.