“The Farming Rules for Water state that soil testing is required every 5 years for cultivated agricultural land. This includes any land which has received fertiliser or manure in the last 3 years.”
Soil tests are carried out for a multitude of reasons, but the main reason is usually to help plan nutrient inputs for the next crop.
Each year when planning the amount of fertiliser required, it is important to think about testing your soils. We would recommend to test soils every 4 to 5 years (if not doing so already). However, testing soils annually to determine the residual soil nitrogen (giving an accurate SNS), will allow alterations to be made to fertiliser recommendations. This will result in applications to the crop to be planned more accurately and any wastage avoided.
At CXCS we have been providing the paperwork for many Environment Agency (EA) inspections and every inspector has requested copies of soil tests for each field. You must be able to demonstrate you are carrying out soil tests and using them to plan your crop applications and are properly assessing the nutrients within the soil.
Phosphates
Phosphates are macro-nutrients within the soil which means that they are required in larger quantities than micro-nutrients. However, soil tests are still required to determine phosphate levels as they can easily build up within the ground, which then takes a long time to be utilised by future crops.
It can take up to 10 years or more to lower Phosphate indices on fields, so it is important not to keep applying phosphate once the indices reach the required level, unless you can demonstrate that the crop will remove more phosphate than what is being applied.
Very few crops have a requirement for phosphate applications at an index of 3 and none have a requirement where the index is over 3. In some rare circumstances, a FACTS qualified advisor may be able to provide you with justification for applying further phosphate to fields with high indices, but otherwise there is no requirement to apply any further phosphate to fields with an index above 3, meaning there should be no applications of manure to these fields.
Why is Phosphate harmful to aquatic life?
When sediment or manure run off enters clean watercourses, it can lead to a build-up of phosphate in the water which encourages algal and aquatic plant growth. This is called eutrophication, and the excess plant/ algal growth strips oxygen from the water, leading to a reduction in fish and other aquatic species living in the watercourses.
Sulphur Deficiency
If visual signs of potential sulphur deficiency can be seen when looking over crops, it may be worth carrying out a specific sulphur test. This would not be shown during the standard 4-yearly recommended testing.
If the soil is lacking in sulphur, then the ground will struggle to uptake the nitrogen applied. Therefore, if applying just nitrogen to fields/ crops, there would be considerable wastage which would negatively impact profits and your carbon footprint, not to mention the increased pollution risk to fields.
For further help and advice on soil testing please contact us on 01981 590514.
