Weed flora in a long-term reduced tillage trial, “Tilman-org session”
LAURA ARMENGOT, ALFRED BERNER, PAUL MÄDER, FRANCESC XAVIER SANS
Abstract
Reduced tillage techniques are widely applied, but mainly under herbicide based cropping systems. The potential increase of weed infestation due to the non-inversion of the soil is one of the main obstacles for their adoption among organic farmers. This study analyses the weed abundance and community composition of a nine-year old experiment under conventional and reduced tillage in organic farming. The experiment was settled in Frick (Switzerland) in 2002 and the crop rotation consisted of winter wheat, sunflower, spelt, 2 years of grass-clover, silage maize, winter wheat, sunflower and spelt. The results did not show huge differences in weed infestation between both tillage systems, although they were higher under reduced tillage, mainly in crops sowed in high-spacing rows, such as the sunflower. However, an increase of the perennial species was observed in all the crops over the years under reduced tillage.
Key words: perennial and grass species, crop rotation, weed community composition weed species richness