agriculture Article Weed Species Trait Selection as Shaped by Region and Crop Diversity in Organically Managed Spring Cereals Merel A. J. Hofmeijer 1,2,*, Bo Melander 3 , Jukka Salonen 4 , Anneli Lundkvist 5 , Livija Zarina 6 and Bärbel Gerowitt 1 1 Crop Health Group, Faculty of Agricultural and Environmental Sciences, University of Rostock, Satower Strasse 48, 18051 Rostock, Germany;
[email protected] 2 Farming System Ecology Group, Wageningen University and Research, Droevendaalsesteeg 1, 6708PB Wageningen, The Netherlands 3 Department of Agroecology, Aarhus University, Forsøgsvej 1, DK-4200 Slagelse, Denmark;
[email protected] 4 Natural Resources Institute Finland (Luke), Tietotie 4, FI-31600 Jokioinen, Finland; jukka.salonen@luke.fi 5 Department of Crop Production Ecology, Swedish University of Agricultural Sciences, Ulls väg 16, 75651 Uppsala, Sweden;
[email protected] 6 Crop Management Department, Institute of Agricultural Resources and Economics, Zinatnes 2, LV-4130 Priekuli, Latvia;
[email protected] * Correspondence:
[email protected]; Tel.: +31-(0)-6-28350597 Abstract: Weeds remain a challenge in organic arable farming, as well as supply ecosystem services. The aim is to control weed densities while hosting a diverse and manageable weed community, preventing domination of few deleterious species. Therefore, we want to understand how specific species are stimulated, and which traits are selected for. This study focuses on crop diversity hypothesizing that (1) regions and (2) crop diversity function as filters for specific weed species traits. Citation: Hofmeijer, M.A.J.; Melander, B.; Salonen, J.; Lundkvist, We conducted a weed monitoring in spring cereals over 2 years on organic farms in five northern A.; Zarina, L.; Gerowitt, B.