NIAB TRIALS POINT TO EARLY WEED REMOVAL
As many growers seek to battle bigger grass weeds this spring, results of new NIAB trials, in partnership with Syngenta, have shown the essential importance of targeting ryegrass and wild oats early with Axial® Pro, to cut crop competition and deliver a sustainable reduction in weed seed return.
Based on the findings from new NIAB research, it is clear using Axial® Pro to remove the largest overwintered weeds at the first opportunity is by far the most important strategy to reduce crop competition and minimise long-term seed return.
Trial results last season revealed winter wild oats that germinated with the crop in October weighed an average 17g dry weight (DW) at GS39 of the crop, compared to 4.5g from a February germinated weed.
Even at a relatively low weed population of 15 plants per m2, that would equate to over 9 t/ha of additional green biomass competition for the growing crop from earlier germinated overwintered weeds.
Forward crops with large wild oat presence this season
Taken through to maturity, the October germinating wild oats produced an average 270% more biomass compared to February germinating weeds, highlighting the hugely greater capability of early germinating weeds to set more viable seed.
Assessed for the impact of later March germinating winter wild oats, the competitive biomass of the weeds was just 3% that of the earlier emerging weeds, and at maturity they averaged only 2.4g DW per plant.
It also confirmed that delaying AXIAL Pro application to wait for later germinating grass weeds offered very little additional benefit in reducing competitive biomass or subsequent weed seed return.
Later application may also require a higher rate of herbicide to effectively kill the larger weeds, as well as making them harderto hit amongst the denser crop canopy.
Early removal of grass weeds is paramount to protect yield, and to minimise seed return in a sustainable weed control strategy.
Where wild oat plants are still smaller than GS30 and actively growing, AXIAL Pro at a rate of 0.6 l/ha will give the most cost-effective control. Once plants get beyond GS30, the rate should be increased to 0.82 l/ha.
Early ryegrass and wild oat removal will ensure that nutrients applied to support this season’s strong crop growth and yield potential can be fully utilised by the intended crop, and not wastefully feeding weeds.
Pete Hawkins
With this season’s forward crops, growers and agronomists can also simplify and complete agronomy programmes more effectively by tank mixing AXIAL Pro with MODDUS® PGR and trace element manganese, for example. Trials have shown complete wild oat control from tank mixes or sequences with various PGR treatments.
Now there is a real opportunity to reinforce previous years’ integrated grass weed strategies to control both ryegrass and wild oats.
For more information visit: www.syngenta.co.uk/grass-weeds
AXIAL® Pro and MODDUS® are Registered Trademarks of a Syngenta Group Company. AXIAL Pro (MAPP 19010) contains pinoxaden. MODDUS (MAPP 15151) contains trinexapac-ethyl. Use plant protection products safely. Always read the label and product information before use. For further product information, warning phrases and symbols refer to www.syngenta.co.uk. ©Syngenta UK Ltd. February 2023.
As many growers seek to battle bigger grass weeds this spring, results of new NIAB trials, in partnership with Syngenta, have shown the essential importance of targeting ryegrass and wild oats early with Axial® Pro, to cut crop competition and deliver a sustainable reduction in weed seed return.
Based on the findings from new NIAB research, it is clear using Axial® Pro to remove the largest overwintered weeds at the first opportunity is by far the most important strategy to reduce crop competition and minimise long-term seed return.
Trial results last season revealed winter wild oats that germinated with the crop in October weighed an average 17g dry weight (DW) at GS39 of the crop, compared to 4.5g from a February germinated weed.
Even at a relatively low weed population of 15 plants per m2, that would equate to over 9 t/ha of additional green biomass competition for the growing crop from earlier germinated overwintered weeds.
Forward crops with large wild oat presence this season
Taken through to maturity, the October germinating wild oats produced an average 270% more biomass compared to February germinating weeds, highlighting the hugely greater capability of early germinating weeds to set more viable seed.
Assessed for the impact of later March germinating winter wild oats, the competitive biomass of the weeds was just 3% that of the earlier emerging weeds, and at maturity they averaged only 2.4g DW per plant.
It also confirmed that delaying AXIAL Pro application to wait for later germinating grass weeds offered very little additional benefit in reducing competitive biomass or subsequent weed seed return.
Later application may also require a higher rate of herbicide to effectively kill the larger weeds, as well as making them harderto hit amongst the denser crop canopy.
Early removal of grass weeds is paramount to protect yield, and to minimise seed return in a sustainable weed control strategy.
Where wild oat plants are still smaller than GS30 and actively growing, AXIAL Pro at a rate of 0.6 l/ha will give the most cost-effective control. Once plants get beyond GS30, the rate should be increased to 0.82 l/ha.
Early ryegrass and wild oat removal will ensure that nutrients applied to support this season’s strong crop growth and yield potential can be fully utilised by the intended crop, and not wastefully feeding weeds.
Pete Hawkins
With this season’s forward crops, growers and agronomists can also simplify and complete agronomy programmes more effectively by tank mixing AXIAL Pro with MODDUS® PGR and trace element manganese, for example. Trials have shown complete wild oat control from tank mixes or sequences with various PGR treatments.
Now there is a real opportunity to reinforce previous years’ integrated grass weed strategies to control both ryegrass and wild oats.
For more information visit: www.syngenta.co.uk/grass-weeds
AXIAL® Pro and MODDUS® are Registered Trademarks of a Syngenta Group Company. AXIAL Pro (MAPP 19010) contains pinoxaden. MODDUS (MAPP 15151) contains trinexapac-ethyl. Use plant protection products safely. Always read the label and product information before use. For further product information, warning phrases and symbols refer to www.syngenta.co.uk. ©Syngenta UK Ltd. February 2023.
