Including spring crops into the rotation has proved the most effective technique in controlling blackgrass, according to the latest results from Frontier research.

In the first year of the four-year project, spring wheat sown in February showed results of seven blackgrass heads/sq m in June 2012, which was a considerable reduction from winter sown crops with ranged from 220 heads/sq m to 513 heads/sq m.

The spring wheat also produced comparatively good yields compared with the winter crops. Lower overall costs of production and a much lower potential of blackgrass seed return have made it the highlight of the first year of the trial.

Project leader Chris Harrold said he is encouraged by the results and it’s not only the spring crops that are faring well.

“The plant and head count figures for this year have shown some encouraging differences. For example, delaying drilling from mid September until mid October in autumn 2011 resulted in a 44% reduction in the number of blackgrass heads/sq m in the crop. This is a significant reduction given the lack of rain at the trial site last autumn,” he said.

“The plant and head count figures for this year have shown some encouraging differences. For example, delaying drilling from mid September until mid October in autumn 2011 resulted in a 44% reduction in the number of blackgrass heads/sq m in the crop.”
Chris Harrolk, Frontier

Yields also benefited from the delayed drilling. Autumn sown crops have yielded on average 1.9t/ha more where establishment was delayed until October.

One of the more surprising results was the comparison between the yields of low seed rate and high seed rate crops with similar blackgrass populations. The higher seed rate showed a greater yield of over 0.5t/ha.

However, caution is needed as these are just results from one season. The focus of the four-year project is to assess the best type of cultural methods that can be used to minimise blackgrass seed return. Mr Harrold says by the end of the four year period there will be a complete picture throughout the whole rotation – not just one season and this will be the key to consistent control and profitability in the future.

More on this topic

Visit our herbicide page for more on blackgrass control