Early distribution and spread of Ambrosia artemisiifolia in Central and Eastern Europe

The introduction and early spread of common ragweed (Ambrosia artemisiifolia L.) in Central and Eastern Europe were reconstructed based on a study of all herbarium specimens of common ragweed deposited at six herbaria in Austria, Hungary and Serbia. More than 450 specimens were examined and the oldest ones, collected from 1907 to 1927, were used to map the historical spread of this highly allergenic invasive weed in this region. The herbarium records back-date the first known introduction of this noxious weed to Central and Eastern Europe as well as its early spread on the Danube-Tisza Plain, and in the North-Eastern part of Hungary. The data also confirm that the introduction of common ragweed to Central and Eastern Europe took place later than its introduction to the Western part of the continent.