More stringent legislation on undesirable mineral losses to the enviro
nment at the farm level creates the need for the farmer to obtain accu
rate information on the mineral flows at his farm, including the miner
al content of manure. Both currently available and recently developed
new sampling methods for slurry and solid manure were tested for bias
and reproducibility in the determination of total phosphorous and nitr
ogen content of the samples. Sampling methods were based on techniques
in which samples were taken either during loading from the hose or fr
om the transporting vehicle after loading. It was demonstrated that mo
st methods were unbiased. New methods for slurry, based on sampling fr
om the hose, were up to a factor two better reproducible compared to e
xisting methods. Sampling of solid manure can be done accurately in a
relatively simple way. For practical reasons mechanisation of sampling
is desirable. To minimize the influence of human activity on the qual
ity of the sample automatization is strongly advisable.