20th March 2020

Are bird repellent seed dressings the only option?

Maize growers will need to rethink their approach to reducing the risk of bird damage following the withdrawal of the principal repellent, but there are options available.

Bird damage can be an issue for some maize growers leading to virtually all maize seed being sold treated with a maize repellent, primarily Mesurol (methiocarb) which has now been withdrawn with only limited Mesurol-treated seed available for 2020 drilling.

But according to Richard Camplin, Technical Manager with LG Seeds, bird repellents may have become an insurance premium rather than a necessity. He says that as all seed has been treated, it is impossible to say if the treatment was actually needed.

“For many farmers, bird repellents may be unnecessary,” Mr Camplin continues. “At our five test sites across the country, we have not treated our variety trials with Mesurol for 10 years, giving a total of over 40 trials. In that time, we lost just two trials completely to birds, with only one other trial substantially damaged. So, it might be that in many cases birds are less of an issue than perceived.

“Like any insurance premium, you only get a return if birds cause damage. If birds aren’t a risk, then all that the treatment has done is increased costs.”

He says that most seed this year will be treated with a replacement bird repellent with the active ingredient ziram and warns farmers to check what dressing has been used.
“Most ziram treated seed will have been treated with the product Korit, although some own brand products have also been used. Ziram has some particular risks and seed must be handled carefully and the appropriate personal protective equipment used at all times when handling ziram treated seed.

“When opening the seed bags and when filling or emptying the seed drill hoppers, avoid exposure to dust and avoid the transfer of dust from the seed bag into the seed drill hoppers.

“The bags themselves will need careful handling and disposal. Do not leave empty bags lying around and dispose of them in accordance with current legislation. Return all unused treated seeds to their original bags and do not reuse empty bags for other uses.”

It is likely that there will be further restrictions on seed treatment use. Mr Camplin suggests there are alternative approaches that can be used to avoid the investment and risks associated with bird repellents and still ensure good crop establishment by working with the plant. He says choosing a variety with good early vigour, focusing on seed bed preparation and encouraging strong early root growth will help reduce the risk of bird damage.

“If we can get the plant away growing strongly and quickly, we can manage the bird risk. Many varieties including Glory, Prospect, Pinnacle and Reason combine excellent performance with exceptional early vigour. As a rule of thumb, consider a variety with an early vigour of at least 7.3 using the BSPB/NIAB list to help with selection.

“Once you have chosen the variety, then focus on getting the seed bed right to encourage germination and root development.”

He advises where possible choosing south or south west facing fields with free draining soil. Create a fine, firm seedbed with no clods and minimize compaction. Seed should be drilled at uniform spacing to promote even germination.

“Seed depth is a big topic of discussion. Drilling deeper can offer some protection against birds but may delay crop emergence. While a depth of 7cm is optimum, it may be necessary to drill deeper to around 10cm. The key is to ensure the soil has warmed up before seed is drilled. You want the soil to have been 8-10°C at the target drilling depth for at least a week before drilling. Clearly the deeper you drill the later this can be and this year soils may take a while to warm up given how much rain we have seen and with more fields waterlogged.”

Mr Camplin says new generation biological seed dressings offer significant benefits and will help ensure plants get away quickly. They also have none of the risks associated with chemical treatments.

Starcover, which is available with most LG maize varieties this season contains a polymer and a biological compound which together have a significant impact on root and plant development.

“The polymer in Starcover seed treatment attracts moisture to the seed. In doing so it changes the environment in which the roots emerge from the germinating seeds and causes more rapid and prolific root growth, particularly the fibrous roots which are more effective at moving water and nutrients into the plant.

“The biological component of Starcover is a Plant Growth Promoting Rhizobacteria (PGPR) which colonises the roots as they grow and increases the availability of soil nutrients to the plant, particularly the increased nutrient supply results in better growth”

Roots on Starcover treated plants shown to be much bigger.

In trials over several years at sites across the country, Starcover treated crops have had 18% more roots that untreated plants. Two weeks after drilling treated plants were on average 5.1% higher and 15.4% higher five weeks after drilling, meaning they were capturing solar energy more efficiently sooner.

When harvested, treated plants yielded between 3-7% more dry matter per hectare and forage was on average up to 2.6%DM higher.

“Biological dressings offer a safe alternative to traditional chemical treatments, although they work in a different way. Rather than being seen as an insurance premium you spend in case of a bird risk, they can be seen as an investment in a stronger plant and potentially a bigger crop.”

However, Mr Camplin points out that most seed this year will be treated with Korit (ziram) and he urges farmers to make sure they brief their contractors about the seed treatment used.

“With a wider range of seed treatments being used this year and more product names, every farmer has a duty of care to make sure the contractor knows in advance what seed treatment has been used so they can take steps to ensure the Health and Safety of their drivers and provide necessary PPE. Click here to download the Safe Handling Guidelines

“Don’t assume they will know which product has been used and make sure the contractor has access to relevant safety data sheets which will be on the bag.”


Watch how Starcover works!

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