1. Pro's and con's of reduced tillage in maize with respect to weeds Rommie van der Weide Hilfred Huiting, Piet Bleeker en Marleen Riemens

2. Why reduced tillage? Which reduced tillage systems? Research and results First conclusions Future Content

3. Why reduced tillage?

4. Economic advantages: Fuel savings (15 till 80%) Less labour (till 60%) Less machinery costs (but first new investments) Higher supporting power of the soil On term savings in nutrients

5. Less emission of CO 2, N 2 O, CH 4 Extra carbon in the soil up to 0.2 t. ha -1. y -1 C Better drought tolerance (1% o.s. = 150 m3/ha) Better water infiltration and less erosion (>90% by no till and >60% by non inversion tillage) Better surfacewater quality through less superficial emission of nutrients and pesticides Less emission of CO 2, N 2 O, CH 4 Extra carbon in the soil up to 0.2 t. ha -1. y -1 C Better drought tolerance (1% o.s. = 150 m3/ha) Better water infiltration and less erosion (>90% by no till and >60% by non inversion tillage) Better surfacewater quality through less superficial emission of nutrients and pesticides Environmental advantages:

6. Creating More Competetive Alternatives and Tecnologies: Sustainable Farming In Brasil Creating More Competetive Alternatives and Tecnologies: Sustainable Farming In Brasil Efficiency: Fuel Ploughing = 1 lt for 50 kg kernels No Till = 1 lt for 96 to 123 kg kernels Nutrition: NPK Ploughing = 1 kg for 15 kg kernels No Till = 1 kg for 26 kg kernels Efficiency: Fuel Ploughing = 1 lt for 50 kg kernels No Till = 1 lt for 96 to 123 kg kernels Nutrition: NPK Ploughing = 1 kg for 15 kg kernels No Till = 1 kg for 26 kg kernels

7. Loss of organic matter in convencional, but increase with no till Loss of organic matter in convencional, but increase with no till

8. Which reduced tillage systems?

9. Ploughing and culture measures Ploughing and seedbed preparation are important measures with respect to weed control Economic and environmental benefits result in increased reduced tillage (95 M ha) (New) technical developments thereby serving the weed control (e.g. ridge till Cloutier, 2007)

10. In the Netherlands non inversion tillage in some areas If needed loosening the soil in autumn cultivation in various ways, often in combination with a powered tool (harrow or cultivator)

11. Ridge tillage in Canada/USA (permanent ridges)

12. Ridge tillage Before and after sowing on permanent ridges and sowing machine

13. Physical weed control in case of crop residues

14. Strip tillage machinery (Dutch Pol/Kuipers)

15. No till and direct seeding: Loosening the soil by: increased soil fauna rooting (green manure) crops Soil coverage for: erosion prevention weed control possibilities for precision spraying Loosening the soil by: increased soil fauna rooting (green manure) crops Soil coverage for: erosion prevention weed control possibilities for precision spraying

16. Research and results

17. Objectives to investigate the usability of ridge till /no till systems as recently developed in the US and Canada for Dutch conditions; to investigate the interaction of tillage system, weed control method and green manure crops choice; to investigate the consequences for weed control, crop protection and economical and environmental aspects.

18. In 2009 start multiple years experiment maïze in Lelystad (EL&I and SPF) Before several years grassland at marine loam soil Start with main treatments (in 3 replicates): Ploughing Ploughing with a caterpillar Non inversion tillage Ridgetill No till Experimental strips with f.e. strip tillage Sub treatments: 4 different green manure crops and no/weedy in fallow period Two different weed control methods Experiment total 180 fields on 2 ha.

19. Mechanical weed control

20. Results 2009 ObjectWeed control Rel. fresh yield (57.7 t/ha) Rel. dry yield (18.9 t/ha) Rel. VEM yield (18.5 t/ha) % (weed) cover PloughingChem. 100 6 Mech. 104 100 9920 N.I. tillageChem. 105 107 1063 Mech. 104 107 10529 Ridge tillageChem. 102 106 10520 Mech. 100 103 10237 No tillChem. 90 88 2 Mech. 91 90 35 Strip tillChem. 100 106 107 Strip till no RRMech. 86 87 8940 Strip till no RRMow. 39 43 4275 N.I. till no RRMech. 98 99 9822

21. Results 2010 ObjectWeed control Rel. fresh yield (53.0 t/ha) Rel. dry yield (17.5 t/ha) Rel. VEM yield (16.2 t/ha) % (weed) cover PloughingChem. 100 0 Mech. 96 101 1022 N.I. tillageChem. 98 105 1062 Mech. 93 96 956 Ridge tillageChem. 88 95 974 Mech. 84 95 977 No tillChem. 83 92 914 Mech. 79 89 6 Strip tillChem. 87 93 949 Strip till no RRMech. 65 73 7872 Strip till no RRMow. 55 60 6683 N.I. til no RRMech. 92 99 10118

22. Weed cover % with different green manure crops: ObjectTreatmentRye Oilseed rape No/ weedy grass/ cloverHairy vetch ploughchem.0.3 2.31.3 mech.0.3 21.32.3 NI tillagechem.1.722.33.77.3 mech.1.7274.65 Ridgetillchem.5.62.92.610.75 mech.3.37.668.35.7 No tillchem.2.73.75.76.37.4 mech.2.33.33.756

23. First conclusions

24. Several soil cultivation systems gave comparable yields in case the green manure was killed with Roundup. No till resulted in yield reduction during the first years. For organic farming non inversion tillage instead of ploughing is possible. Mechanical equipment should be adapted to green manure residues on the soil surface (e.g. moving harrows). No till and strip till are difficult to manage organic and avoid yield losses. More weeds left in case of non inversion tillage (2-3 times) instead of ploughing in the second year. Also green manure crop choice influences weed pressure (less after rye and oilseed rape).

25. Reduced tillage systems will gain importance in Europe because of economic en environmental contraints. The different opportunities need to be optimized and compared on a longer time scale, not only concerning yields, weeds and economics but also on the environmental effects. Precision techniques (for sowing, nutrition and crop protection) can be used for further improvement. Future:

26. Thank you for your attention, discussion and (further) support! © Wageningen UR

27. Relative VEM with different green manure crops: ObjectTreatmentRye Oilseed rape No/ weedy Grass/ cloverHairy vetch ploughchem.100109107100116 mech.107108110112106 NI tillagechem.111114115111116 mech.9710210996104 Ridgetillchem.9710411099108 mech.10210497104108 No tillchem.9098103 93 mech.9989959693

28. First calculations energy usage in MJ/ha Object Ploughing630 Non inversion606 No till215

29. C C Infiltration 80 40 20 0 0 100 Conventional Tillage Conventional Tillage * *