Report on the 1st EU
Weed Mapping Workshop in Prague
May 13th to 15th 2009


Weed surveys have a long tradition in many European countries. Finland, Hungary and the Czech Republik have started with new initiatives this or last year. Unfortunately, many results of previous surveys in many central and eastern European countries are either not accessible or not published in English yet. The software used and the documentation of data varies from country to country. For some areas, no data are available at all. Most existing weed maps show the distribution of weeds only. They don’t refer to a ranking of weeds nor to the severity of weed infestations. Around 30 colleagues met at the Czech University of Life Sciences on May 14th in Prague to get a first overview on weed mapping activities in Europe. They discussed aspects of different interest groups: mapping of weeds on arable land, on non-arable land, rare weeds, invasive weeds, e.g.. 12 oral and two poster presentations were provided.

After a general introduction by Hansjörg Krähmer, three Czech scientists, Samuel Lvoncik, Michaela Necasova and Pavel Hamouz described their programs which use Turboveg for Windows, a freeware provided by the Masaryk University of Brno. All Czech relevés are based on the Brown-Blanquet scale. Istvan Dancza and Guyula Pinke reported on the long lasting experience with weed surveys in Hungary. Hungarian groups have especially concentrated on invasive weeds such as Ambrosia artemisiifolia, Iva xanthiifolia or Asclepias syriaca recently. Weed surveys use more than 200 defined sites to guarantee continuity. More than 2000 relevés were produced between 1947 and 2008. Maria Zajac explained Polish activities and referred to the ATPOL database and the Flora Cracowiensis Secunda where 1547 species are recorded. Albinas Auskalnis introduced the audience to Lithuanian agriculture and to weed surveys dating back as far as 1957. Apparently, weed spectra changed with agronomic practices. The Serbian activities were reviewed by Maja Meseldzija. GIS based recordings and maps produced with the Serbian Ambrosia Spot Marker software were presented. Terho Hyvönen is involved in a Finish weed survey program that started recently. Plant density and seed bank studies are part of this project. Baruch Rubin discussed Israeli studies using Verbesina encelioides as a model species. ArcView 9.1 was used to prepare maps. He referred to Flora of Israel Online where data of weeds are available. Dario Massa and Martin Weis test different software packages and databases for the storage of geodata. One model project is the mapping of herbicide resistant weeds in Germany in cooperation with Proplanta. Bärbel Gerowitt summarized weed mapping activities of the Rostock University in cooperation with BASF and Syngenta especially in oilseed rape. Finally, Bernd Laber from Bayer CropScience presented maps of herbicide resistant biotypes mapped with ArcGIS. Two posters by Michael Glemnitz on the methodology of assessing weeds were on display. The great interest of the group in more weed mapping information resulted in the proposal of establishing a new working group within the EWRS.

Regional coordinators were proposed to involve more colleagues for the update of first existing maps:

T. Hyvönen and A. Auskalnis: Scandinavia and Baltic countries
J. Recasens+N.N.: Spain, Portugal, France and Italy
M. Zajac+A.Auskalnis: Poland, Belarus and Ukraine
S. Lvoncik+M.Necasova: Czech Republik, Slovenia, Slovakia and Austria
B. Rubin+N.N.: Israel, Turkey, Jordan, Egypt and Greece
Kristin Goerke: Germany, Benelux, Great Britain, Switzerland
I. Dancza+N.N.: Hungary, Romania and maybe Moldova
M. Meseldzija: Croatia, Bosnia, Montenegro and maybe Bulgaria


On May 15th, J. Soukup and his crew organised an interesting field trip with an overview on Czech cropping systems and important weeds.

Hansjörg Krähmer