Soil management and grassland rejuvenation

Tuesday 14 August 2012

Over 40 people attended this event in August at Monkfoss Farm, Whitbeck, near Millom, by kind permission of JS & IM Wilson, organised by The Farmer Network and funded by the RDPE North West Livestock Programme. Programme.

The day began with a presentation by soil specialist, James Bretherton of AgScope on “The secrets in the soil,” and he began by taking a spade sample from the field and examining the soil structure and content, including taking a good sniff to identify whether the sample was aerobic (sweet smelling and healthy) or anaerobic.

James explained that soil is made up of minerals (salt, silt, clay approx 46%), air (24%), water (24%), and organic matter (5 – 7%). Furthermore he explained that soil needs organic matter to live ‘the living component’, the presence of this being a good indicator of soil health.

Organic, he explained was the key to good soil and could be measured by sampling the soil. Loss of air in the soil was the problem with intense arable farming, due to over-ploughing, which releases carbon and destroys organic matter. Soil health directly influences the mineral content, necessary for soil fertility and though iron is necessary, too much locks up copper and other minerals.

Potash is another mineral that is often too high in the soil content, spoiling its function and this mineral has increased by over 40% since the year 2,000, by over application of fertilizer and slurry, thus a need to build up organic content, possibly by adding green waste. Too much slurry also kills the soil by starving it of air and killing off bacteria which need to breathe, while poaching and too much heavy machinery are other destructive factors.

Concluding, James stressed the importance of the presence of worms in the sample, a good indicator of healthy soil, with lots present in permanent pasture.

Helen Mathieu of British Seed Houses then discussed grassland rejuvenation and grass seed varieties, suggesting that good grassland management could reduce the need for higher acreages through reseeding and choosing the correct varieties to suit farming needs, depending on soil types and climate.

She explained that grass has evolved to suit particular climates and may suit that environment but may not be massively productive. Productivity depends on the percentage level of perennial rye grass which utilizes all the available organic matter (it is dark green grass with red at the base of the tillers). She further explained about the three different types of rye grass and their suitability:-

- Italian, being a short term variety, aggressive but with no staying power – lasts 2 years only
- Hybrid, a cross between Italian and Permanent, grass, a dual purpose – medium term giving hybrid vigour and extending the life to 3 – 4 years
- Perennial, used for re-seeding for 4 years or more.
Another grass she recommended for sheep and wet areas was ‘Timothy’, which had a feed value of only 5% less than rye grass.
Helen further suggested soil testing on a regular basis and if fertility is good then rye grass will predominate. Further she recommended monitoring types of grass present, including clover and how many bales produced, a good indicator of which fields are falling down in grass production. Soils, she explained, deteriorate for many reasons including:-
- Natural
- Soil structure – organic deterioration
- Over/under grazing
- Poaching
- Poor Management

Concluding Helen told farmers that they could make more use of their land by re-seeding rather than renting more land. Grass and clover lays put in four times as much protein as soya and small differences make big financial gains. Before lunch farmers watched two demonstrations of soil aeration and slot seeding.