The Farmers Mart Apr-May 2019 - Issue 62

22 FARM BUILDINGS & EQUIPMENT APR/MAY 2019 • farmers-mart.co.uk MAINTAINING A CLEAN, PEST-FREE SILO DAVID Cross, Head of Technical Training, Rentokil Pest Control and Paul Casson, Technical Field Man- ager, Rentokil Specialist Hygiene Silos are an attractive envi- ronment for rodents and stored product insects (SPIs) given the abundance of flour, sugar, maize, grain and animal feed they typ- ically hold. Rodents might even be tempted to nest and shelter in these tall structures – a wor- rying thought for the agricultural industry, who need to conform to stringent food health and safety requirements. It’s crucial to take the right steps to prevent pests from enter- ing these structures in the first instance, and to ensure you can detect an infestation at the earliest stage, should one occur. Given that silos contain food products or the raw ingredients for food pro- duction, which may be for human consumption once manufactured, strict legislation is in place to en- sure that workers and managers follow best-practice food safety regulations. Silos are tall, complex struc- tures, and it is therefore easy for food stuffs to accumulate in hard- to-reach places. A deep cleaning strategy should feature high on the radar of all silo managers; as it is a powerful weapon in prevent- ing pest infestations, and a must immediately after any contam- ination issue. It also plays an important role in ensuring a silo is operational all year round. Stopping rodents in their tracks Rodents carry and spread infec- tions that could put the produc- tion line at risk. Salmonella, Han- tavirus and Weil’s disease are just three examples of the diseases they could bring into the silo. Rats and mice can contaminate silos with urine, faeces and hair – as well as cause substantial damage through gnawing. This can lead to an increased risk of fire to any facility if their presence is unde- tected as they may gnaw through or damage electrical cables. Altering the habitat surrounding the silo to make it less attractive to rodents is a key preventative step. Even if the silo itself is well-sealed, the surrounding buildings can play their part in attracting rodents if they are not sufficiently main- tained. Here are some top tips to help you implement a proactive pest control strategy in any agri- cultural facility: 1. Seal any gaps: Mice are capable of squeezing through gaps the size of a biro to enter premises, so seal holes in the exterior of the silo or surrounding buildings with wire wool, caulk, metal kick plates or cement. Rats are also known to enter buildings through damaged drains, so it’s important to make sure that any entry points or vents are well maintained and checked regularly. If you’re unsure how rodents could be entering a building, don’t hesitate to ask pest control experts to analyse the site and make recommenda- tions. 2. Remove any clutter and food sources: Storage con- tainers or clutter in structures around the silo provides rodents with a place to hide, so it’s worth moving these away from walls if possible. Make sure food and waste containers are also ade- quately sealed. Mice can take food from up to 70 different sources in 24 hours, so plac- ing bait for them can prove challenging. Rentokil has de- veloped RapidPro Riddance (containing the rodenticide alphachloralose), which kills a mouse after just one feed of the trap’s lard-based solution. This is a fast-acting rodenti- cide, meaning the deceased mouse will typically be found close to the bait and can be disposed of easily. 3. Quick detection: Non-toxic monitoring blocks are another way to detect rodent activity as early as possible, while en- suring toxic substances aren’t deployed unnecessarily onsite. Some of these blocks contain fluorescent mate- rials which reflect UV light, highlighting rodents’ drop- pings and making it easier to identify their presence. any external contractor, part of their role is to be proficient in the latest legislation chang- es in their area of expertise. Pest controllers are no differ- ent; if in any doubt as to what substances you can and can’t use, or how to use them, then it’s always best to check with the experts. Working with a specialist hygiene team Stored Product Insect infestations The most common SPIs are grain weevils (Sitophilus grana- ries), rice weevils (Sitophilus ory- zae), saw toothed grain beetles (Oryzaephilus surinamensis), flat grain beetles (Cryptolestes Spp) and flour beetles (Tribolium Spp). All of these can be responsible for the spoilage of ingredients – espe- cially those developing from egg to adult, which can consume large amounts of food. Farmers and food manufactur- ers storing grain or grain-based products in bulk can suffer the unwelcome consequences of these infestations. Risks from an SPI infection include 1. A major loss of revenue as a result of loss of product weight 2. SPI-infested grain that was destined for human consump- tion can be downgraded due to a reduction in its nutritional value 3. Serious blockages or damage to machinery as a result of webbing, which is produced by larvae as they feed 4. Infected grains are liable to become warmer, accelerating insect problems and leading to problems with damp, mould and even grain germination 5. Produce can become con- taminated by insect waste 6. Non-compliance with legisla- tion can lead to commodities being rejected The key is to identify and treat an infestation at the earliest stage. Fortunately, there are some steps you can take to identify and man- age SPI infestations: • Use cone traps, probe traps and floor traps: Place these around the building, to give a good early warning sign of any activity. • Look out for bore holes and dust tracks: Emerging adult weevils and grain borers will leave visible exit holes in the grains. You may be able to spot insect tracks in flour or grain dust around the silo building. • Phosphine gas treatment: The most effective way of controlling an infestation is to fumigate the product with phosphine gas, widely used with cereal products. This is a cost-effective treatment that will not taint the product. • Consult the experts: Phos- phine gas is heavily regulated, so if you’re dealing with an SPI infestation, it’s important that you know who to contact. For Cleaning these enormous struc- tures is challenging and it requires specialist work, which can inter- rupt everyday processes. To mini- mise disruption, it’s recommended that they are serviced with the help of a specialist hygiene team. The team tackling a silo clean must be fully trained in confined space entry, emergency rescue, as well as the use of the correct ac- cess and safety equipment, such as gas monitors and escape kits. Using the correct ATEX-rated equipment is of paramount importance, es- pecially when working with dusty food stuffs such as flour, as any spark from electrical equipment has the potential to ignite dust and cause an explosion. Unfortunately, this is a very real possibility, and one that is realised every year throughout the world. Using a specialist company is the wisest option when you consid- er the ramifications of not doing so. Technicians will be trained in recognising the differences of how to clean structures used by various commodities. For example, sugar can set like concrete, while flour is prone to clinging onto the side of the silo. At other times a thick layer of flour can become suspended or ‘bridged’ in mid-air, when the top layer has set, and the flour beneath is emptied out. Final words Silo managers and specialist cleaning teams should work closely together to implement a regular and thorough cleaning routine. Ensuring the silo is regularly cleaned will mean pest activity is minimised, and product spoilage doesn’t become an issue. A frequent and consistent approach will ensure financial and reputational costs to the business don’t become an issue, and that the silo is productive all year round.

The Farmers Mart Apr-May 2019 - Issue 62 | Page 22