Dairy Production
Potassium is essential for sustaining productive pastures, and so potassium fertilisers are an important element in dairy farming systems. Potassium is particularly important for sustaining the legume component of mixed pastures - and a diminishing proportion of legume species can be a sign of depleted potassium.
Fertiliser timing
The timing of potassium fertiliser application can affect the total annual pasture production, as well as the distribution of production throughout the year. Split applications of potassium fertiliser are recommended if high annual rates of potassium are used (>100kg/ha) in high rainfall areas, or where soils are prone to leaching.
Potassium losses
The removal of animal products such as meat and milk is only responsible for a small proportion of overall potassium losses within the dairy system. Potassium can also be lost through leaching, runoff and soil fixation, and in transfer of dung and urine to non-productive areas of the farm like stock camps and yards. Transfer losses increase with the intensity of the farming system, and can make up a large proportion of potassium loss within dairy systems.
Grass tetany
Adding potassium fertiliser
to pastures has been associated with the incidence of grass tetany (also
called hypomagnesaemia) in dairy cattle. This metabolic disorder develops
when insufficient magnesium is absorbed from the diet. However, strategies can be
adopted to minimise the risk of grass tetany while ensuring maximum pasture
production.
Move on for more information about:
Pasture
Production and Composition >>
Timing
of Fertiliser Application to Pastures >>
Potassium
Loss Mechanisms >>
Grass Tetany >>
Potassium
Deficiency Symptoms >>