When slurry is processed in a biogas plant, organic nitrogen (N) is partially mineralised to ammonium (NH4+), which increases the nutrient value. NH4+-N in digested slurry can vary between 60-80 % depending on the digested biomass type. In Denmark, the fertiliser value for N in slurry is set by law to 75-80 %. The fertiliser value of digested biomass might be higher, especially if efforts are made to reduce ammonia (NH3) loss. However, biomasses with a high content of dry matter (DM), e.g. deep litter, straw and energy crops, lowers the nutrient value of the digestates as it reduces the share of ammonium N, and the higher DM con-tent prolongs the time before the slurry infiltrates the soil. This increases the risk of NH3 volatilisation – par-ticularly in combination with the rise in pH which is a side effect of the biogas process. At high DM contents, it is important to use slurry application technologies that reduce this risk e.g. slurry injection, trail hose appli-cation and acidification. Almost half of NH4+-N may be lost as NH3 if the DM% of the digestates is above 8 %. It can therefore be beneficial to ask the biogas plant to separate the digested slurry to reduce the DM content.