Slurry: Do you know what you're working with? - test your slurry and soil for better results

Friday 09 July 2010

IMPROVING slurry utilisation to help save money was the key aim of the demonstration event held on Tuesday 29^th June at Birches Farm, Turton by kind permission of Mr Andy Paton.

The meeting started with a presentation by Mark Tripney of Matrix Ag, a consultant specialising in soil and nutrient management, who opened with the fundamental point that it is the soil that feeds the crop and the fertiliser that feeds the soil.

"It is vital that farmers know the current nutritive value of their soil, and the nutrient content of their manure, before they can begin to plan where manure should be applied and at what rates" - Mark Tripney

He asked the group how many of them actually tested their soil and slurry to get a base line value for the nutrients that they contain, adding that it is "vital that farmers know the current nutritive value of their soil, and the nutrient content of their manure, before they can begin to plan where manure should be applied and at what rates" in order to utilise this resource most efficiently.

Mark then described the ideal structure of soil – 45% minerals, 25% air, 25% water and 5% organic matter – and pointed out that by improving the structure of the soil it is possible to reduce the need for fertiliser as the plants can access the nutrients more effectively.

Many soils have insufficient air in them and can be rapidly improved by incorporating more oxygen through the use of an aerator or sward lifter depending on the depth of the pan (general rule is: grazed sward = shallow pan = aerator; cut sward = deep pan = sward lifter). Increasing the organic matter levels in the soil will also assist in the retention of nutrients by the soil.

Some field soil analyses were then shown to the group which illustrated that fields closer to the farm, which are more easily accessible, tend to have higher N,P and K levels as this is where slurry is often applied on a regular basis, whilst fields that are further away are often deficient. In those soils which are high in potash the grass will exhibit luxury uptake, and high forage potash can lead to chemical imbalances in livestock, particularly a shortage of sodium.

The effect of soil pH was also discussed, with the optimum pH for nutrient availability being 6.2. pH levels higher or lower than this can affect nutrient uptake by plants. For example at high pH levels the element molybdenum is very readily available, but luxury uptake of this can lead to copper being locked up. This can then lead to associated problems in the livestock consuming the forage - such as infertility.

Mark concluded by showing the group some calculations of potentially how much money can be saved by applying slurry in place of artificial fertilisers. The main take-home points from the presentation were:

Use soil, slurry and forage analysis to create a base line of what you have to work with
Slurry is a rich source of nutrients but targeting it towards soils which have a low nutritive value will ensure that it is utilised most efficiently rather than the nutrients being wasted.
The correct soil conditions are vital for plant growth. Dig a hole in the soil in order to determine if there is panning present and if aeration would be beneficial.

Why Muck Matters: Click Here to view Mark Tripney’s presentation from the event

The afternoon session was spent with the farmer groups rotating around various workstations:

Liz Russell and Paul Rogerson of EnviroSystems spoke about the ongoing research work into the effect of SlurryBugs on the nutritive value of slurry and its environmental benefits. For more information about the work they are carrying out and the research findings follow the link http://www.envirosystems.co.uk/
Bolette Neve of Tried and Tested gave an overview of the paper-based system of nutrient budgeting and answered any queries or questions that farmers had. For more information follow the link http://www.nutrientmanagement.org/
Kevin Ormisher, a local agricultural contractor, brought along a slurry injection system and explained to the group the financial and environmental benefits of using this system of slurry application as opposed to more conventional methods.

Rachel Price of FWAG was testing slurry samples, brought by farmers to the event, in order to analyse the nitrogen content, using a Quantofix Nitrogen Meter. Once farmers know the readily available nitrogen content of their slurry it is possible to plan more precise fertiliser and slurry applications.

Many farmers were surprised by the results as they were so variable and wide ranging.

As part of the Northwest Livestock Programme, Promar International is carrying out Nutrient / Manure Management Planning

The planning looks at maximising the use of slurry and manure and reducing the use of fertilisers without compromising grass growth. Includes soil sampling. CLICK HERE for further details.