Exceptional turnout for the first South West Potato Day
Despite inclement weather, the first South West Potato Day (April 26 at Frogmary Green Farm, South Petherton, Somerset) was a big hit with growers arriving from as far afield as Cornwall.
More than 70 delegates engaged with the speakers concerning practical information on subjects such as reducing greenhouse gas emissions and the latest news from the Metaldehyde Stewardship Group.
Adding extra nitrogen to the soil as ‘insurance’ can make tubers delay bulking and reduce yield, so it makes economic sense to ensure quantities applied are accurate, said ADAS principal research scientist Ken Smith. He noted that although the potato industry has a relatively low carbon footprint, nitrous oxide emissions (another greenhouse gas) from soil are strongly influenced by manure and fertiliser applications, and this is an area that may come under scrutiny in the future.
Dr Smith also recommended growers use the Potato Council’s Crop nutrition for potatoes and Defra’s Fertiliser Manual (RB209) for good rule-of-thumb guidance on nutrient contents of FYM in addition to having their soils analysed regularly. “It is a good idea to keep records of soil nutrient levels in the soil to build a bespoke database for their own land,” he said.
“If nitrogen rates are too high, the result can be delayed tuber initiation, excessive/persistent canopy and delayed skin-set, plus possible increased losses to the environment. Particular care is needed with poultry manure which is like ‘rocket fuel’ – it can be more potent than you think.”
Although up to half the national crop receives organic manure of some type each year, relatively little is used effectively, and growers could shave pounds off their fertiliser bills with the help of accurate and quick nutrient analysis of organic manures.
Dr Smith reminded growers of the technique using near infrared reflectance spectroscopy (NIRS) to analyse manure which was recently developed with Potato Council R&D support in collaboration with other AHDB divisions. “This test is inexpensive compared with laboratory charges and only takes a few days. It can really help to make the most of organic manures, which is good for profits and for the environment.”
Simon McMunn, commercial manager of De Sangosse Ltd and spokesman for the Metaldehyde Stewardship Group discussed the importance of the slug pellet active metaldehyde to the industry. Today the group represents 100% of the metaldehyde slug industry in Britain.
Drawing growers’ attention to problem areas, he explained that after a detailed review of how slug pellets are used, applied and handled, areas needing attention were identified. These included storage and handling practices, packaging and transportation facilities.
“One of the major achievements of the Stewardship Group has been the significant investment that is now taking place to improve all these areas”, said Mr McMunn. “We have built up best practice guidelines that are available on our website www.getpelletwise.co.uk. We have also significantly influenced the need for trained operators and anyone applying slug pellets now needs PA1 and SPS or PA4S.
“The use of best practice is crucial, and key guidelines include a maximum level of active per hectare to avoid drainage and runoff losses. This is set at 700g of active ingredient/ha per calendar year, with additional restrictions in place between August and December.
“Moreover, pellets should never be applied within six metres of a water course or when heavy rain is forecast.”
Mr McMunn warned that the maximum annual rate is particularly important in potato crops if followed by a cereal crop, which is also likely to demand slug pellet treatment.
He also emphasised that correct timing of slug control helps to reduce populations of the pest and mitigate environmental damage.
“The rule of thumb is to start slug control at 75 per cent canopy complete for first application, but you also need to use slug traps to gauge thresholds. At four slugs per metre your yield may already be compromised, so you will need to take control measures.”
The afternoon session was informal, with delegates showing great interest in the new George Moate Tillerstar on show in the yard, as it was too wet to hold a field demonstration.
Paul Goddard, Bayer Application and Stewardship Manager also showed the updated Digimon controller designed to facilitate calculation of the correct calibration for powder applications to prevent rhizoctonia and maintain high accuracy of applications within plus or minus five per cent.
“At planting, ensuring an even and consistent cover of powder treatment to prevent Rhizoctonia solani can have a very positive impact on marketable yield,” says Paul Goddard, application and stewardship manager for Bayer CropScience, who led a recent joint Bayer-Potato Council workshop on powder application.
“An insufficient dose reaching seed tubers can risk unnecessary disease development, and what isn’t on the seed tubers is a waste of product that is also undesirable in the wider environment if the treatment is off-target, he emphasised.
These risks can be reduced by using a dedicated, correctly calibrated applicator.
“Using applicators is recommended as being best practice as it conforms to industry stewardship standards. It is the most efficient means of applying the product as it achieves an even coverage over the tubers.”
Summing up the day, Potato Council director Rob Clayton reminded growers that feedback about the first South West Potato Day is vital, and growers can choose the topics they would like to see at events next year.
“Our industry has a fabulous future and we’re sustainable. We’ve reduced inputs and we use water efficiently, so we are well placed to forge ahead,” said Dr Clayton. “Many thanks go to Branston Ltd and Greenvale AP for being our partners at the South West Potato Day, and to our hosts Nick and Claire Bragg. These local potato days are becoming increasingly popular, and we hope to announce soon the date for the first Cornish Potato Day, planned to take place in 2013.”
For more information on Potato Council events go to www.potato.org.uk/events
For information on NIRS go to www.ahdb.org.uk/projects/Stoneleigh.aspx