Harvest Weed Seed Control Project Results

Harvest Weed Seed Control Results

Below you will be able to find the project results from both Year 1 and Year 2. If you have any questions, please contact info@bofn.org.uk.

Project Overview

Over the last 2 years, we have been working with Redekop and NIAB to explore harvest weed seed control (HWSC) in the UK as a method to control grassweeds and reduce dependence on chemical control. It aims to help farmers establish reasonable expectation of what proportion grassweed remains at harvest and available to SCU (or other similar control measure).

Make sure to give this video a watch to find the results and join the seed circle to stay updated about what is coming next!:

Project Results: Seed Scout Focus

The Harvest Weed Seed Control (HWSC) project, led by Driver Farms, aims to help farmers establish reasonable expectation of what proportion grassweed is left standing at harvest and available to Seed Control Units (SCU’s) (or other similar control measures). 

The project involved four farmers (see below) who had SCUs fitted to their combines, working with Will Smith from NIAB who drew up a protocol for assessing weeds and efficacy of the SCU.

Once the protocol was finalised, BOFIN recruited 42 Seed Scouts who received seed-sampling packs. These included full-instructions on how to carry out the protocol and guided them to videos on the BOFIN YouTube channel to provide further assistance. This enabled them to get a reliable indication of how much weed seed is shed between full ear emergence and when the combine cuts the crop.

As you can see in the chart above, there were 5 types of grassweeds sent into the lab at NIAB. It was noted that the most common grassweed sent in was blackgrass, with around 20-25% of the seed still in ear at harvest. It was found that Italian ryegrass had 40-50% of seed still intact which was slightly underwhelming as previous research indicated this number to be 70-80%. Similar results were found with meadow brome with only 50% of seed left intact. Sterile brome had around 40% of seed still in ear and wild oats, as little as 5%. 

Although these results give such great indications of what can be expected from the different grassweeds at harvest time, Will did point out that “although a nationwide survey was conducted, it did only consist of 25 samples being returned. In order to build a more reliable and comprehensive database, it is imperative that farmers continue to get involved.” 

An important part of the HWSC project was to understand how the results gathered from the seed samples could indicate the importance of the use of harvest weed seed control measures, such as the SCU.

Project Results: Seed Control Unit & Trialist Focus

Controlling weeds at harvest is a novel concept in the UK so to explore the potential further, farmers and researchers have been trialling the Redekop Seed Control Unit (SCU) technology over the past two years in a bid to expand the non-chemical options for weed control available to UK growers. The technology, which is well proven across Canada, the USA and Australia, enables the milling of chaff to a fine dust, found in independent trials to destroy up to 98% of harvested weed seeds, such as meadow brome, blackgrass, and ryegrass. Trial work in the UK was initiated by the British On-Farm Innovation Network (BOFIN), in partnership with NIAB, and funded by Redekop. This is the first time it has been trialled in a maritime climate.

Initial work was carried out at NIAB’s farm near Cambridgeshire with the technology fitted to a Case IH 7230 in a field with high meadow brome and wild oat burdens.

The second year of research saw the technology rolled out onto commercial farms, all with varying weed pressures. The results – 83% weed reduction in the following crop of blackgrass seed retained in winter wheat, brome populations significantly reduces. See below for our Redekop SCU trialists:

Fuel usage
The three trialist farmers noted anecdotally that this increased about 10% with the SCU engaged, which reflects experience from other parts of the world.