Walnut

Walnut family. In the wild it grows in the mountainous regions of Central Asia, Transcaucasia, the southern part of the Balkan Peninsula, Iran, China, Korea and Japan.

In the wild it grows in the mountainous regions of Central Asia, Transcaucasia, the southern part of the Balkan Peninsula, Iran, China, Korea and Japan.

Reaches 30-35 m in height, trunk from 1 to 1.5 m in diameter. A tree with a comparatively small crown, solitary trees with a broad, pyramidal crown. The bark of young trees is glossy, olive-gray, later deeply longitudinally fissured. Leaves pinnate, up to 40(75) cm long, of 5-11 leaflets, the size of which decreases from the tip of the leaf toward the base.

The terminal unpaired leaflet is larger than all the others and on a short petiolule, the rest are sessile. When the leaves are crushed a pleasant smell is noticeable. Male flowers are in catkins at the base of leaves on last year's shoots, female ones at the tips of young shoots. The fruit is a drupe with a fleshy green husk, which withers and blackens on the tree. The husk cracks when ripe while still on the tree. The seed is enclosed in a bony, wrinkled shell of two valves joined by a projecting ridge.

Relatively shade-tolerant, approaching hornbeam and linden by this measure, significantly more shade-tolerant than oak. Varies greatly in frost hardiness. For good development it needs deep, fertile, sufficiently moist soil with the presence of calcium. Propagated by seeds sown into the ground after collection or in spring after stratification. Forms and cultivars are propagated by grafting and by layering of suckers. The suckering ability is retained into great old age.

Besides its fruit-bearing value it has high ornamental qualities: vigorous and rapid growth, tolerance to adverse urban conditions, longevity.

It has many forms, among which the following are of decorative interest: by crown shape - weeping (f. htndula), fruiting (f. fertilis); by leaf shape - single-leaved (f. monophylla), variable-leaved (f. heterophylla), dissected-leaved (f. laciniata), narrow-leaved (f. angustifolia), broad-leaved (f. latifolia), ash-leaved (f. fraxinifolia); by leaf coloration - variegated (f. variegata), striped (f. striata); and less interesting ones - by character of inflorescences, flowering time, size and shape of fruits, hardness of the shell. Also of interest are its hybrids with other species of the genus: with black walnut - (J. x intermedia Dtpp.), with gray walnut - (J. x intermedia alata Cair.), (S. x silvosteposa N. Vech.) and with the Manchurian walnut.