First report of Thladiantha dubia in Croatia
Thladiantha dubia (Cucurbitaceae) is a climber vine native to Northern China. This plant has been cultivated in Europe from the second half of the 19th century and it escaped from cultivation to establish populations in Central and South-Eastern Europe. The species is known to be established in Austria, Germany, Hungary, Lithuania, Poland, Romania, Russia, Serbia and Slovakia, and to be casual in Czech Republic, Italy, and Ukraine although its exact status is not always clear. It climbs up shrubs along railways, riverbanks; it also grows in maize fields, on the borders of vineyards and on waste deposits. T. dubia is considered invasive in Japan, whereas in Europe, it is not considered to be spreading or invasive, except in Austria where it is recorded as harmful to maize production.
The plant was reported for the first time in Croatia in Zagreb in the Savica area, a complex of small eutrophic lakes. T. dubia was found in nitrophilous, ruderal habitats, i.e. in strongly disturbed stands of floodplain forests of willows and poplars. The population is relatively large and consists of a few hundred individuals climbing on neighbouring trees and shrubs, covering approximately 100 m2. The species mainly reproduces vegetatively through tubers, and it is not known if this dioecious species can reproduce sexually. T. dubia is thought to have entered Croatia through contaminated soil. Although the species is considered as non-invasive, it could be usefully monitored.
Sources
Alegro A,Bogdanović S, Rešetnik I, Boršic I (2010) Thladiantha dubia Bunge (Cucurbitaceae), new alien species in Croatian flora. Natura Croatica 19, 281-286.
DAISIE Species factsheet – Thladiantha dubia