Mechanical behaviour of three organic fertilisers to optimise spreading methods in the vineyard

Organic viticulture is attracting increasing interest worldwide. Fertilisation can be carried out with different products, such as manure, the solid fraction of digestate and compost. In order to optimise the distribution rate, it is very important to previously check the physical characteristics of these materials, which are typically subjected to progressive compression during the spreading procedure. In this context, the use of dedicated sensors and specialised software devoted to piloting the rotors and bulkhead speed of the spreader is highly recommended, taking into account also the different rheological characteristics of the different matrices. A series of laboratory tests to determine the load-deformation curve were arranged. The results showed that digestate and manure behaved in a similar way, but the former was more compact with the same load. [Publisher's text].