Quercus robur - English Oak

Quercus robur, also known as the English Oak, common oak, or pedunculate oak, is a powerful and majestic tree that populates our forests in Europe. This noble species, has an irregular and airy crown, massive and tortuous branches located towards the bottom of the trunk, beautiful deciduous foliage that provides pleasant shade, and numerous acorns that delight small animals. Wide and tall, it grows faster than the sessile oak once established and can reach a venerable age. Perfectly adapted to our moderate climates, its large development requires plenty of room to grow in a spacious garden.

The English oak belongs to the Fagaceae family. It is native to a large part of temperate Europe. It appreciates sub-oceanic to oceanic climates, or continental climates without excess and relatively humid. In its natural environment, it can reach a height of 50 m (164 ft) with a span of 25 m to 30 m (82 ft to 98.4 ft), while its trunk can measure up to 2 m (6.6 ft) in diameter. In our gardens, it will reach an average height of 27 m (88.6 ft) with a spread of 20 m (65.6 ft). With a quite exceptional longevity, this oak can live up to 2000 years according to some estimates. Deciduous oaks have the advantage of producing good and abundant soil, favourable to the growth of plants that germinate under their cover.

The growth of this oak is moderately fast. Its habit is massive, slightly less wide than tall. The trunk, quite short, is covered with initially green and smooth bark, then becomes dark, thick, and deeply fissured. The crown is irregular, rounded, and open in shape. Its young branches are glabrous, grey-brown in colour, and shiny. The foliage, late deciduous, consists of alternate, soft, obovate leaves that can reach 5 cm to 15 cm (2 in to 5.9 in) long and 3 cm to 8 cm (1.2 in to 3.1 in) wide. Each leaf is divided into 5 to 7 pairs of asymmetrical rounded lobes, separated by relatively deep sinuses. The base of the lamina is narrow and has 2 small lobes. The colour of the lamina is a dark greenish-blue on the upper side, with the lower surface being paler. The leaves turn brown quite late in autumn, and remain slightly attached to the branches before falling. The flowering of this oak occurs in April-May, shortly after the appearance of the foliage, on annual shoots. The female flowers are placed in a cupule carried by a long peduncle: this distinctive characteristic is the origin of the species name, pedunculata. The male inflorescences are elongated, pendulous catkins, tinged with yellow. They are produced on older branches. The female flowers give way to ovoid and elongated acorns, measuring 1.5 cm to 3 cm (0.6 in to 1.2 in) in length. They are often grouped in pairs or threes and attached to a long peduncle. A cupule covered with scales covers one-third of the acorn. The colour changes from green to brown at ripeness, in September and October. The root system of this tree is deep and powerful, both taproot and extensively spreading, thus providing a solid and durable grip in deep and compact soils.

The English oak should be protected and preserved if it is spontaneously present in a park or a large garden, if only for the symbolism that surrounds an aged subject, a true keystone of an old garden. It can be planted either individually or in rows, in a very large garden. It also provides pleasant shade, which reflects light in winter. Its fruits, sometimes produced in abundance, feed small animals such as squirrels and jays. It can be planted with, for example, maples, plane trees, hackberries, lindens, and sophora in a large park.