Selectivity of weed harrowing with sensor technology in cereals in Germany
- Publication Type
- Contribution to conference
- Authors
- Rueda Ayala, Victor and Gerhards, Roland
- Year of publication
- 2009
- Published in
- Proceedings of the Joint International Agricultural Conference
- Editor
- C. Lokhorst and J.F.M. Huijsmans, R.P.M. de Louw
- Pubisher
- Wageningen Academic Publishers , Wageningen, Netherlands
- Band/Volume
- JIAC2009/
- Series/labeling
- ECPA (European Conference on Precision Agriculture)
- ISBN / ISSN / eISSN
- 978-90-8686-114-9
- Page (from - to)
- 339-348
- Conference name
- Joint International Agricultural Conference
- Conference location
- Wageningen, Netherlands
- Conference date
- 6.-8. Juli
Three field experiments were installed to investigate whether intensity, timing, and direction of post-emergence weed harrowing in winter and spring cereals influenced the selectivity. Selectivity was studied as originally defined in Denmark. Each experiment was designed to create various intensities by increasing number of passes angle tine and driving speed, applied at varying crop growth stages. Objective estimation of leaf cover through differential image analysis was used. A recent proposed statistical procedure was used to analyse the effects. Selectivity was in general influenced by timing of harrowing. Improving effects were seen at late crop growth stages, when harrowing was aggressive enough according to the season. Leaf cover and weed density decreased exponentially at increasing harrowing intensities. That caused an increment of crop soil cover, although not always improving weed control. Harrowing across crop rows did not cause impacts on selectivity, while along rows seemed to improve it at early growth stages. Nevertheless, further research is needed to prove the results. Sensors to estimate leaf cover index and soil resistance, were tested to generate algorithms to automatically adjust in real-time the harrow to a determined intensity. Intensities which generate the crop soil cover percent associated with the higher selectivity will be taken as the basis to develop algorithms.