Farm composting put to the test (From Gazette & Herald)

Farm composting put to the test

EASTBURN Farm, Driffield, was the venue for the latest Forward Farming demonstration, which centred on the composting of farmyard manure.

The farm is in the process of converting to organic production, and the host farmer, Derek Megginson, is keen to make best use of farm waste and improve soil fertility in the absence of artificial fertilisers.

Mr Megginson explained that composting - the decomposition of organic materials by bacteria under controlled conditions - requires careful management. "The material must be provided with sufficient oxygen to encourage the right type of bacteria and the temperature should be maintained at about 50C," he stated. A probe thermometer is used to monitor the composting process.

The critical temperature for killing weed seeds is 63C, but if temperatures rise much higher than this, the bacteria is killed and the composting process stops. Turning the heap both introduces more oxygen and prevents the compost from over-heating.

A tractor-mounted composting machine was demonstrated, turning the long narrow piles or windrows. Mr Megginson described how the mixing effect ensures that the materials compost evenly and it also tends to break up larger lumps, increasing the surface area for the bacteria to work on.

A typical composting time for manure using the turning machine is two months, at which point the windrow no longer re-heats after turning and the compost is left to mature or spread on the fields. The resultant compost is not only a rich source of plant nutrients, readily available to plants, but is also biologically active. Improvements to soil fertility and structure are expected, but the windrowing system is labour intensive and Mr Megginson has yet to confirm the economic benefits.

The potential environmental benefits are substantial.

Forward Farming arable demonstrations are co-ordinated by Bishop Burton College and details of future events can be obtained from Bill Meredith on (01964) 553000

Updated: 11:24 Wednesday, July 23, 2003