(Quercus petraea (Matt.) Liebl.)
Habitus
- a high tree growing up to 30 m
- the crown is egg-shaped in solitary trees broadly spreading, but less branched than that one of the English oak (Quercus robur)
- in the stand, the crown is set higher (smaller)
- the trunks are ± straight, the bark is brown-gray, later gray, smooth
- the bork is brown-gray to blackish, longitudinally cracked into flat rectangular plates, less firm than that one of the English Oak (Quercus robur)
Buds
- the buds are arranged in a spiral, clustered at the tip around the terminal bud, but less than in the English Oak (Quercus robur)
- the buds are 6 - 12 x 4 - 5 mm in size, pointed, and slimmer than those of the English Oak (Quercus robur)
- in other characteristics, they are similar to those of the English Oak (Quercus robur).
Shoots
- they are relatively thick, longitudinally ribbed, olive green to reddish-brown
- the lenticels are raised, dotted, and whitish
- overall they are similar to the English oak (Quercus robur)
Leaves (assimilation organs)
- the leaves are simple, elliptical, feathery-lobed, 8-12 x 4-7 cm in size, widest in the middle, lobes are blunt, and the edge is entire
- lateral veins open only into the lobes !
- the upper side is dark green, glossy
- the underside is lighter, with hairs only in the axils of the veins
- at the base, they taper off!
- the petiole is 1-3 cm long, longer than that of the English oak (Quercus robur), distinctly groove-like in cross-section
Flowers
- monoecious tree with flowers of different sexes
- it blooms in May simultaneously with the unfolding of leaves, but about 14 days later than the English Oak (Quercus robur)
- the flowers are morphologically similar to the English Oak (Quercus robur) with the difference that the female (♀) flowers are on short stalks or almost sessile
Fruits – seeds
- the fruit is 1.5 - 3 x 1-2 cm large, barrel-shaped acorn (gland) widest in the lower third, compressed at the end when ripe, brown, without darker bands
- the cupule is brown, thin-walled, scaly, shortly stalked, almost sitting
- germination is like in that one of the English Oak (Quercus robur)
Extension
- it was originally spread in a smaller part of Europe than the English Oak (Quercus robur), but unlike it, the Sessile Oak (Quercus petraea) does not occur in the eastern part of Europe
- in Slovakia, it grows from the lowest positions on average up to an altitude of 680 (max. 1,145) m above the sea level
Ecology
- it is a light-loving tree species, less demanding on soil fertility and moisture than the English Oak (Quercus robur)
- it grows on acidic and alkaline soils
- in terms of moisture requirements, we recognize two ecotypes of the Sessile Oak (Quercus petraea):
- woodland steppe
- growing in habitats with a higher groundwater level
- it forms stands with the European Hornbeam (Carpinus betulus), and more prominently with the European Beech (Fagus sylvatica); in the optimum area of distribution, it also creates ± homogeneous oak forests.
Significance
- similarly to the English oak (Quercus robur), the wood is of even higher quality
- the fruit-bearing tree, with acorns, it is a significant source of food for forest animals and birds, especially during the seed year
- the ecotype of the Sessile Oak is known - Kokošovský (Quercus petraea - kokošovský), characterized by a straight trunk and exceptionally high-quality wood. For this reason, in 1965, a "National Nature Reserve Kokošovská Dubina" was declared on an area of 20 ha, where mainly preserved Sessile Oak forests with the original high-quality variety of the so-called Kokošovský Sessile Oak are protected. According to historical records, ships of Christopher Columbus were built from the wood of these oaks.
