Optimization of manure application can have 2 economical incentives which are to obtain optimal yields of high product quality and to save money by reducing mineral fertilizer inputs. On an ecological point of view manure application optimization can avoid ground and surface water pollution, excessive nutrient enrichment in soil and excessive ammonia and odour emissions (particularly as odour emissions related to manure application can be smell further than odour emissions from building of manure storage). The most important options to optimize nutrient efficiencies and to reduce odour and ammonia emission are the following: fertilization done according to the crop requirement for N, P, K by limiting the application rate to the first element satisfied (generally P for swine manure) and using mineral fertilizers to complete the other elements requirements, land application shortly before the time of the crop’s main nitrogen requirement, using favorable weather conditions (no frozen soil or snow cover, wet and cold), when possible rapid incorporation after spreading finally the use of application techniques which reduce odour and ammonia emissions.

General information is given on ways to optimize manure application economically and ecologically. These considerations are basic elements to be considered in landspreading. However some of the information given has to be applied to European conditions where the winter is in many areas more mild than in North America.