CROATIAN FLORA, Oriental Plane Tree in Trsteno

The Oriental plane tree (Platanus orientalis L.), from the plane tree family (Platanaceae), is a deciduous tree with an irregular, sparse crown, typically reaching heights of 30 to 40 meters. The bark is smooth and mottled in shades of brown and grey, peeling off in large patches; in old age, it becomes grey, plate-like and finely cracked. The root system is very strong and extensively branched, penetrating deeply and widely into the soil and ensuring the tree’s stability. The leaves are simple, alternate, thinly leathery, 10 to 30 cm long and wide, palmately divided into five, less commonly three or seven, sharp lobes that narrow at the base and have deeply and coarsely serrated margins. In autumn, the leaves turn brown or dark reddish-brown. The flowers are inconspicuous, unisexual, and arranged in hanging globular inflorescences. Flowering occurs in April, simultaneously with leaf emergence. The fruits are small, dry, inverted-cone-shaped nutlets with tufts of brown hairs at the base. They remain on the shoots throughout winter and disintegrate on the tree during the first warmer days of spring. The Oriental plane tree is monoecious and heliophilous (light-loving) and can live for several hundred years. It grows rapidly and is often cultivated as an ornamental tree, valued for the shade it provides along roads and in urban parks. It is most commonly found in the Mediterranean and the Orient, and in Croatia, primarily in the coastal region. The plane tree on the square in Trsteno has been protected as a monument of park architecture – an individual tree – by a decision of the Nature Protection Institute of the People’s Republic of Croatia dated 24 January 1951 (Official Gazette Nos. 80/19, 15/18, 14/19 and 127/19). It is 12.80 meters tall, and its age is estimated at just over 500 years. According to tradition, the plane trees were planted at the beginning of the 15th century by Captain Florio Jakob Antunov, known as Indian, who, inspired by the beauty of the Bosphorus plane trees during his travels, brought five saplings of the Oriental plane tree to Trsteno and planted them near a water source. To this day, only two monumental trees have survived, the plane tree on the square and one in a private garden, primarily thanks to the favorable climate, the nearby water source, and the care of local residents, who bequeathed responsibility for the trees to their heirs. Today, these two monumental Oriental plane trees represent a scientific and cultural link and are a symbol of Trsteno as well as of Croatia’s national natural heritage. They are among the largest plane trees in Europe and Croatia. Given their age, trunk dimensions and growth form, these two trees are unique specimens of their species even on a European scale. Mirela Uzelac Božac, mag. oecol. Assistant at the Institute of Agriculture and Tourism, Poreč