Letters Rules Stop Greater Green waste use

Rules stop greater green waste useYour article Net spreads benefits of green waste (Machinery, Mar 25) identified many benefits of using compost in agriculture and correctly concluded that there needs to be considerable up-take by the farming community if government targets for landfill diversion and recycling of organic waste are to be met. Compost, biosolids, in the form of sewage sludge, some industrial wastes and animal manures all have a potential part to play in the provision of readily available and slow release major, minor, and micro-plant nutrients. As well as providing soil conditioning properties that improve workability, reduce erosion and improve water retention, properly integrated into a farm fertiliser plan, the use of these materials can also realise significant savings in the artificial fertiliser bill. Sadly the use of these materials and some of their inherent agricultural benefits are restricted by maximum application rates of 250, 210 or 170 kg/ha of total nitrogen depending on a farms NVZ status and cropping regime. Total nitrogen is the sum of the inorganic nitrogen (ammonia, nitrate, and possibly nitrite) and the organic nitrogen (urea, proteins etc.) The inorganic forms of nitrogen are all water soluble and are therefore readily available for plant up-take or could leach into ground or surface water if applied at the wrong time or in an inappropriate way. The organic fraction however is stable and is available only for plant up-take once it has been converted to an inorganic water-soluble form following mineralisation. Regulations should not be over complicated or restrictive and should acknowledge the difference between inorganic and organic nitrogen. Les Sharp Red Lane, Huxley, Chester