Costly cultivation choices for black-grass control
Balancing black-grass control with economic agronomy is a difficult challenge for every different farm situation.
Cultivation and establishment trials at the Syngenta Black-grass Focus Site have demonstrated that ploughing, followed by a comprehensive herbicide programme, did achieve the all-important 98% overall black-grass control to effectively manage populations, reported Syngenta Field Technical Manager, James Southgate.
"That directly compared to 91% black-grass control in crops established by direct drill and 92% from min-till cultivations, with the same herbicie programme," he said.
However, ploughing delivered a slightly lower yield – of 11.19 t/ha – and had far higher establishment costs, at £147/ha, compared to £58 for direct drilled crops.
Overall it resulted in a lower margin over establishment costs of £1364 for the plough, compared to £1508 with min-till and £1571 from direct drill.
“The question for individual growers is whether the better black-grass control from the plough warrants the potential financial cost,” according to James.
“That will depend from farm-to-farm, or even field-to-field, but we can now put a cost on the calculation.”
The trials have also shown that delayed drilling, to the beginning of November, for example, could have a huge impact in reducing the grass weed burden, compared to the end of September, and enable the pre-em herbicide to have a really good effect. Drilling date would also have an impact on the establishment techniques selected, added James.
Long-term trials by Syngenta grass weed specialists, at the company’s Black-grass Focus Site, at Barton in Cambridgeshire, have provided some crucial insights into combinations of herbicide and cultural options to manage grass weeds at economically viable and sustainable levels.