The Value of Soil Analysis
Byline: SEAMUS McMULLAN, Beef and Sheep Development Adviser, Greenmount College
FERTILISER is one of the main costs on beef and sheep farms in Northern Ireland.
Over the coming grassland season it will be important to produce grass as cheaply as possible using the correct type and quantity of fertiliser without harming the environment.
Before designing a suitable fertiliser programme it will be necessary to establish the existing level of soil fertility.
Soil analysis is a reliable and cost-effective method of measuring soil fertility and should be carried out at this stage of the year, before slurry or inorganic fertilisers are applied.
MAIN NUTRIENTS: The main nutrients required for satisfactory grass growth are nitrogen, phosphate and potash.
While grass yield depends mainly on the quantity of nitrogen applied it is also dependent on adequate phosphate and potash being available.
Although nitrogen is either used up quickly or leached from the soil, phosphate and potash are not so easily leached and they can build up in the soil when high levels of slurry or compound fertiliser have been applied.
LIME: Soil acidity is another important factor in maximising grass growth.
It is measured by the lime status or pH of the soil. A poorly limed, acid soil discourages productive ryegrass and clover varieties and tends to encourage less productive grass species such as creeping bent and Yorkshire fog.
It is important to remember that lime is being continually leached from the soil by rainwater and must be replaced when the soil pH falls to a critical level. …