The Summer Oak is a big desiduous tree, belonging to the Beech family. The oak reaches a height of 25-35 meters, and some even up to 40-50 m, with a trunk diameter of up to 2 meters. Its crown is large, wide, starting low on the trunk. The color of the bark of the old trees is grey-brown. It is cracked and thick. The young branches of the oak are bare and ridged, with several buds developed on them.
It blooms along with its foliage in the months of April and May. It forms beautiful fruits called acorns, a much-loved food by wild boars, squirrels, mice and other forest dwellers. The fruits grow up to 5 cm large, have short stalks on which they grow up to 4 in number. As raw they are colored in light shades of green, and then become shiny and brown.
The Oak could live over 1000 years. In the Stara Zagora area are found two trees, from which one is 1637 years old and the other over 1000.