Weed survey of spring cereals in Finland, 2007 - 2009

The data originate from national monitoring on the effects of the Finnish agri-environment support scheme (MYTVAS). The weed flora in conventionally and organically grown spring cereals was investigated in southern and central Finland during 2007-2009. The survey was conducted in 16 regions, 283 farms and 595 fields (72 organically cropped and 523 conventionally cropped fields, of which 503 were treated with herbicides). The occurrence and density of weeds were assessed during a 4-week period starting in mid-July (weeks no. 28/29), by which time the spring cereals had reached their heading stage. The methods are described in the following publication: Salonen, J., Hyvönen, T. & Jalli, H. 2011. Composition of weed flora in spring cereals in Finland – a fourth survey. Agricultural and Food Science 20: 245-260. Similar weed surveys in spring cereal fields have been carried out in Finland three times since 1960s, the third survey in 1997-1999 (see: Salonen, J., Hyvönen, T. & Jalli, H. 2001. Weeds in spring cereal fields in Finland - a third survey. Agricultural and Food Science in Finland 10, 4: 347-364.)