Business Rural Summer 2021

| 29 Overseer accuracy called into question Central Southland crop and sheep farmer Russell Laughton is a long-time advocate for fine particle fertiliser. Russell Fredric MEAT & WOOL » Russell Laughton “The plant gets everything into its root system virtually instantly.” • NEW & USED SALES • PARTS & ACCESSORIES • MX APPAREL IN STORE • FARMLANDS CARD WELCOME Invercargill’s Polaris Dealer 03 214 4838 212 Bond Street, Invercargill A long-time advocate for biological stimulants and fine particle fertiliser is concerned about the Government’s ability to accurately deter- mine nitrogen limits. Central Southland crop and sheep farmer Russell Laughton says fine particle liquid fertiliser is the answer to many environmental issues currently faced by New Zealand farmers. However, he believes the government has a one size-fits-all approach to measuring nitrogen limits under its National Policy Statement for Freshwater Management (NPS) and National Environmental Standards for Freshwater. Fine particle fertiliser application involves mixing fertiliser into a slurry which is applied on pastures by centrifugal force, much the same as solid ferti- liser, but it doesn’t dissolve into the ground to the same degree because it sits on the foliage, Russell says. Russell uses Magnify NZ (formerly known as Biohelp NZ) products to optimise the response he gets from applied fertiliser and is pleased with the result he is getting on-farm. The two main Magnify products used by Russell are Magni-Grow and Magni-Life. Magnify products kickstart, boost and enhance soil biology to produce higher yields, with less disease. Improved soil structure, root development, nitrogen fixation, plant energy and worms are part of the benefits. They simultaneously tackle environ- mental issues – leaching and carbon. Russell and Dawn’s wheat and pasture yields per hectare have improved considerably. The application method that Russell used de- signed to improve the effectiveness of the fertiliser through greater surface coverage, which results in more grass per kilograms of nutrient than can be achieved with solid fertiliser, he says. The process is claimed to improve soil condi- tion, biological activity and plant available nutrient, to reduce leaching by 50%, reduce emissions by 14% and increase water use efficiency by 38%, ultimately resulting in improved dry matter quantity and quality. Russell is among those who have concerns that Overseer, a widely used programme that measures nutrient ground flows as well as being used for nutrient budgets, is not fit for purpose. He believes there is a lack of accurate methodol- ogy to measure the amount of nitrogen applied to an area, especially in the case of fine particle fertiliser, liquid fertiliser or humates are used. “I think they’re basing a lot of it on Overseer and they’re now finding out that Overseer can be big, big percentages out. It’s not really a true guide,” Russell says. A Government-appointed science advisory panel which completed an independent review and as- sessment of the Overseer model agrees. The panel identified a range of shortcomings in Overseer and concluded they did not have confi- dence in Overseer’s estimates of nitrogen lost from farms in its current form. Russell says figures on a computer do not always translate to the reality of what is happening in or on the ground and some Overseer users he knows have cited variances of 30% to 40%. “[Fine particle] is a completely different way of using your fertiliser.” The difference between granulated fertiliser and fine particle fertiliser is that every leaf of clover and every blade of grass has coverage, he says. “That way the plant gets everything into its root system virtually instantly, whereas if you apply granulated fertiliser you’ve got to wait for it to dilute into the ground and then the root system will pick it up from there. Russell and his wife Dawn have farmed their family trust owned 263 hectare property at Heddon Bush, Southland, for 48 years. It has been run by both Russell and his son Malcolm, who is married to Rachel, for more than 20 years, however due to some health challenges Russell has not padded the paddocks so much in the last couple of years. The farm supports about 700 romney/Texel breeding ewes and 200 hoggets, but the greater portion is in crops, including 100ha of winter sown wheat. The balance comprises barley, oats, peas grown for seed, and rape grown for rape seed oil. Reduce nitrogen + leaching We have rebranded Visit our new home formerly Biohelp For soil, plant & animal health 6 farms : 1 appl'n Stan Winter 0800 66 88 100 1000 to 3200 kgDM 3 cents/kgDM extra 12-22%