Common oak is also known as English oak or Irish dair.
It's a large, deciduous tree with a wide spreading crown and deeply fissured grey-brown bark.
Common oak is one of about 600 species of the genus Quercus.
The tree has green, oblong and very short-stemmed leaves with rounded lobes.
Both male and female flowers are found on the same tree.
The green-yellow male flowers are hanging catkins. The pale brown female flowers are inconspicuous and arranged in short, stiff spikes.
The fruits - oval shaped acorns - are 2-4 centimeters long, with a cup that covers one third of the nut.
The acorns are light brown maturing to a chestnut brown colour.
The tree is native to Europe, north Africa and western Asia. It's a long-living species - can be more than 1000 years old.
Common oak grows in almost any type of soil, but thrives best in moist, clayey soil. Grows everywhere throughout Denmark.
Common oak wood is used in hardwood flooring and furniture making, for sculpture carving and wood turning, and in the making of barrels for storing wines and spirits during aging, giving the wines and spirits their distinctive colours and flavours.
The bark is used in dietary supplements - and to tan leather.
Grated or grounded acorns can be roasted and used as a coffee substitute.