Pedunculate oak (Quercus robur)
Appearance: A deciduous tree shedding its leaves for the winter, often very impressive, almost grows up 45 meters high, The crown is wide and high, especially in free-standing specimens, with a beautiful spherical vault, often with very branchy branches, overall, however, more irregular, than the previous species.
Already at a slight height above the ground, the trunk splits into numerous boughs and therefore it is impossible to track to the center of the crown, usually it is also a bit knotty and irregular.
Branches often bent or twisted, very massive.
Light gray or light brown gray bark, also on younger trees with a dense network of furrows and slats. Greenish-brown shoots, initially still hair-like, later more and more balding, often also slightly "frosted"”. Round-oval donuts, with a length of approx 8 mm, pointed, with many scales.
The leaves have 10-12 cm in length and about 8 cm wide, they are obovate, rounded front, and at the base with distinct ears. They have more or less on both sides 5-7 round flaps, which are cut halfway through the lamina and do not face each other. by what a leaf, unlike the leaves of the previous species, seems somewhat asymmetrical. The upper surface of the leaf is dull and dark green, lower side brighter, and the edges are often slightly wavy.
Long-ovate acorns (1,5-2,0 cm in length), in a shallow bowl, usually they grow two or three on a stalk of length 4-6 cm (feature that gives the name).
Habitat: Pedunculate oak grows particularly eagerly on fresh or water-soil soils. It can withstand more harsh climatic conditions than the closely related pedunculate oak.
Occurrence: Widespread everywhere in Europe, but especially in the lowlands from northeastern Russia to southwestern Spain. A very important European forest tree.
Flowering period: May to June.
General thoughts: Age is noteworthy, which are achieved by pedunculate oaks, and which is approaching the upper limit of life expectancy, available for a deciduous tree. Oaks tend to be much older than beeches, as well as linden trees and they can even count themselves 1000 lat. Many old oaks are protected and can only be kept alive with a great deal of work and money. Oak leaves often have growths (fortress), especially rich in tannins. They are caused by specific insects (gallows). Gallic ink was previously made of such gels, which was used for documents, as particularly durable.
If you plot the accurately measured widths of a tree's annual rings on the graph, the picture is obtained, resembling a fever curve. For trees of the same species and area, these curves turn out to be very similar. Therefore, images of wood curves of different ages can be compared with each other. For example, a 300-year-old oak, which was felled in 1984 year provides the curve for years 1684-1984. By comparing the sequence of the widths of the rings of accurately dated pieces of wood, complete graphs can be drawn up many centuries back.. In this way, a two-thousand-year chronology of fir was compiled for Central Europe, beech and oak. With their help, unknown wood can now be dated, for example, from the beam of historical buildings or the wood of antique furniture, the maximum age of which can thus be determined.