Field-scale variability of weed distribution on arable land

Weed mapping was conducted in 2 fields in Central Bohemia to characterize the spatial structure and temporal stability of weed populations over four years (1999-2003). The number of plants for each species and total weed coverage was investigated on each grid point. To determinate the weed infestation variability, the Patchiness-Index was calculated. Using Surfer software, weed maps were created. For a single weed species occurrence the correlation between years was calculated. Results document heterogeneous occurrence of weeds, especially Cirsium arvense, Tripleurospermum maritimum and Galium aparine, whereas Viola arvensis and Stellaria media were distributed more homogeneously. Galium aparine, Viola arvensis and Lamium amplexicaule are characterized by relatively high spatial stability.