As was the case on many farms, Abbots Ripton Farming Company Ltd & Lavenham Fens Farms Ltd saw a reduction in yields on 2020 compared to the long-term farm average. “The farm wheat yield was 9.7t/ha,” says Rupert Waters Farms Manager. “Higher grain prices have helped compensate for lower yields and maintain farm profitability.”
In the Black-Grass Task Force in Action project field, spring barley yielded 5.6 t/ha. There was a a clear difference between the area sown with a cover crop last autumn and the area without. “The cover crop strip had approximately 1 tonne/ha less than the rest of the field.”
The suspected reason for this is the black oats in the cover crop mix releasing compounds called avenocins during decomposition that inhibit the growth of other cereals with spring barley especially affected. This was particularly problematic last season because cover crop destruction was delayed due to wet weather.
The project field will once again be spring barley this season with the cover crop experiment continuing without black oats in the mix. However, the cover was sown later than planned. “In my first year running the farm, we missed the window for getting the cover crop in at the right time and so a late mix went in in the middle of October, I don’t have much hope for it but felt we had to get something in for the sake of the project.
“While the black grass project is on our high land, 75% of what we farm is on fen and fen skirt and while cover cropping and minimal disturbance works in one scenario when growing sugar beet (5-year rotation) and potatoes (10-year rotation) in the rotation the soil is being inverted every three to four years not giving a long enough break from inversion to use the plough rotationally as a tool against black grass. This is an area I will look to explore more going forward.”
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