Pedunculate oak

Family Fagaceae. The best-known representative of the genus, widely distributed in the European part of Russia and Western Europe. Present in many nature reserves of the European part of Russia, the Caucasus, the Baltic states, and the Crimea. Forms oak forests and is part of various types of mixed conifer-broadleaf forests on different but fertile soils. A light-loving mesophyte.

A long-lived, very powerful tree up to 50 m high, in dense stands with a slender trunk highly cleared of branches, when planted singly in open places — with a short trunk and a wide, spreading, low-set crown. The bark on trunks up to 40 years old is smooth, olive-brown, later gray-brown, almost black. Leaves alternate, at the tips of shoots clustered into tufts, leathery, oblong, obovate, up to 15 cm long, with an elongated apex and 3–7 pairs of blunt lateral lobes of unequal length. The lobes are entire, or with 1–3 teeth; at the base of the blade often with auricles. Leaves glossy and bare above, dark green, lighter beneath, sometimes with sparse hairs. Acorns up to 3.5 cm, covered by the cupule for 1/5, ripen in early autumn.

Grows slowly, with the greatest growth vigor at 5–20 years. Moderately light-demanding, wind-resistant thanks to a powerful root system. Does not tolerate excessive soil waterlogging, but withstands temporary flooding up to 20 days. Prefers deep, fertile, fresh soils, but is capable of developing on any soils, including dry and saline. Has high drought and heat tolerance. One of the longest-lived species, living 500–1500 years. Propagated by sowing acorns; ornamental forms by grafting and green cuttings. Regenerates well by stump sprouts.

Among the numerous forms the most interesting are:

а) by crown shape: pyramidal (f. fastigiata) - with a narrow columnar crown. The same crown has pyramidal cypress-like (f. fastigiata cupressoides); pyramidal green (f. fastigiata viridis) - with very dark green foliage; pyramidal golden-spotted (f. fastigiata aureo-punctata); pyramidal silver-spotted (f. fastigiata aigenteo-punctata); weeping (f. pendula); weeping Dauvessei (f. pendula Dauvessei) - with a more pronounced weeping habit; (f. pendula horisontalis) - main branches almost horizontal, terminal ones pendulous; globose (f. umbraculifera);

б) by leaf blade shape: entire-leaved (f. holophylla); heterophyllous (f. heterophylla); fern-leaved (f. filicifolia); comb-like (f. pectinata); spoon-shaped (f. cucullata); deeply-spoon-shaped (f. desseda-cucullata); three-lobed (f. trilobata); curly (f. crispa);

в) by leaf color: purplish (f. purpurescens); dark-purple (f. atro-purpurea); white-variegated (f. variegata); concordia (f. concordia) - with glossy golden-yellow leaves; white-edged (f. argenteo-maiginata); gold-variegated (f. aureo-variegata); marbled (f. marmorata); tricolor (f. tricolor).

Most often the pyramidal form of pedunculate oak is used in landscaping. A tree with a pyramidal crown reaching 8.5 m in height at 25 years of age, with a crown diameter of no more than 3 m. Branches begin growth from the graft union and grow upward at a sharp angle, forming a dense, compact crown. Leaves are firm, dark green, smaller than those of the typical form, densely arranged on the shoots. Frost-hardy, grows slowly, demanding of the soil, drought-resistant. When sowing acorns up to 50% of seedlings inherit pyramidal habit. Propagated more often by budding or splice grafting to the root collar of the main species. Planting to a permanent site occurs in the 5th–6th year after grafting. Used in solitary, group, and avenue plantings, and for creating dense untrimmed screens.

'Concordia'. A tree up to 8–10 m tall (slow-growing), with a rounded crown and glossy golden-yellow leaves. In summer the leaves have a greenish tinge. This form is also called the "variably-golden". Planted as a specimen and in contrast groups, especially effective in groups with coniferous plants. This form is not sufficiently frost-hardy.

'Atropurpurea'. A very interesting slow-growing form of medium size (from 10 to 20 m). Its leaves and shoots are a rich wine-violet color, becoming green-violet at maturity. Pedunculate oak also has other, less common purple-leaved forms. Among them Q. r. 'Purpurascens' with bright purple young leaves that later take on a green color, and Q. r. 'Nigra' with darker purple leaves that retain this color throughout the summer. The cultivar 'Fastigiata Purpurea' has not only an unusual leaf color but also a pyramidal crown form. These forms suffer frost damage, but can grow from the latitude of Moscow southward.

'Variegata' ('Argenteopicta'). This white-variegated form of the widespread pedunculate oak has leaves covered with white spots on a green background.

The typical form is the basis of large parks and forest parks in areas with conditions favorable for its development. Ornamental forms are used in solitary and group plantings. A most valuable species for green construction in all steppe regions and the middle forest zone from the northern boundary of its distribution.

Tree 20–30 m tall. Eastern North America. Grows in a variety of habitats: from dry elevated ridges to moist soils of river valleys (from 0 to 600 m above sea level). Does not tolerate shading. A common tree of broad-leaved forests. In the Botanical Garden since 1976: 1 specimen (3 individuals) obtained as living plants from cultivation. Tree, at 15 years: height 1.5 m, crown diameter 50–110 cm. Growing season from the first decade of May to the end of October–beginning of November. Growth rate medium. Does not flower. Low winter hardiness.