07: Waste disposal methods for Slurry and farmyard manure
At the end of this session you will be able to:
Describe the range of equipment in slurry and FYM spreading.
Explain the correct methods of spreading slurry and FYM.
State the advantages and disadvantages of each machine.
Evaluate their effectiveness in economic and environmental terms.
Organic waste from Livestock
This is described in two ways:
Farmyard manure
Slurry
What happens when FYM or slurry is spread at different times of the year?
Late winter/spring is the best time of year to spread as this is when crops are most likely to be able to take up nutrients. This means that yields are maximised, fertiliser costs are reduced and it minimises nutrient losses to the environment.
If nutrients are supplied during the autumn or early winter, which are not needed at that time, in particular nitrogen, they will be lost through runoff and leaching (especially on shallow/sandy soils).
In the summer there is less risk of leaching, but extra nitrogen is lost from manure applications as ammonia gas.
Avoid high risk times. Applying in late autumn and early winter with high rainfall results in nutrient leaching, runoff and lower soil temperatures which reduce plant uptake.
Use low emission methods in the summer, eg splash plate as high losses of ammonia are common.
Avoid high risk areas. Steep slopes, waterlogged ground and frozen ground should be avoided.
Avoid heavy applications (> 50m3/ha/application should be avoided).
Apply only what the crop needs, check soil indexes and account for nutrients in slurry.
Check that spreaders are calibrated correctly and spread accurately.