Thoughts on Soil and Education.
Looking at fields around the country on my travels, the fields are looking extremely dry, the small amounts of rain we’ve had not really helping.
Meanwhile the flora in the roadside verges are often looking a flourishing green colour. One of the obvious reasons is they’ve not had the tight grazing or cutting that grasses on farms have had of late. But it is also the natural selection of species that allows successful plants to flourish against the deficient of nutrients, for example plantain, red clover, and cocksfoot. The local council have implemented a long interval cutting regime for our verges and as a result we see tremendous regrowth, like our own lawns, as it leaves root systems intact to provide feed and water to the plants
Pic 1. This example of a nearby road verge side showing an array of greenery and biodiversity of white clover, plantain, yarrow, and cocksfoot grass as well as other probably less productive native grasses such as tussock grass.
This non- selective cutting is in fact like non-selective mob grazing, an amount of forage removed in a very short period, now seen as a regenerative method of farming. In a continuous grazing or short rotation grazing regime, then the roots contract and reduce their capacity to feed and water the plants.
To achieve this mob grazing on farm requires a large amount of forage to feed a large number of animals relative to the area of grazing, 500 cows on a hectare grazing on 3 tonne of dry matter wouldn’t be unusual. Periods of rest are important to save the roots from receding, a well preserved root structure is important for soil biology and the root exudates, if undisturbed will enable the plants to grow through dry periods. Disturbance, being tillage or heavy doses of nitrogen fertiliser as this will interfere with mycorrhizal fungi networks and it’s this that signals to the plant to provide nutrients. As more nitrogen is applied so the plants become more hydroponic and needy, you’ve only got to look at a perennial ryegrass plant when it is stressed.
Pic 2 More “neglected " verge -sides
This is next to an area of SSSI, which no doubt helped provide a more exotic range of biodiversity, it includes red clover,birdfoot trefoil and plantain as well as some good old traditional grasses. . The clover providing the nitrogen and the deep roots of the plantain that will trail blaze for other plant roots and worms to colonise even deeper in the soil. They will mine minerals and trace elements for the other plants.
This is how botany works harvesting sunshine, carbon dioxide and water to make carbohydrates or sugars. This, we have all known from biology lessons for years, so what made it seem to fail so spectatacularly ? What made most farmers feel they have to apply fertiliser to areas that can take a tractor and not within any environmental restrictions. Yet areas they are not able to fertilise, regard as poor and not worthy.
I know a farmer because of environmental restrictions who cannot fertilise or reseed his meadows, therefore his opinion of the growing capacity of these naturalised areas of biodiversity is so low, he views his land with contempt and set stocks it, not thinking it worthwhile to do any other grazing system.
This approach is not new and a heavy dependence on inputs has been taught in agricultural colleges for generations. Indeed I was at agricultural college at the time of the Green Revolution, where Nitrogen, Phosphorus and Potash was championed to double plant yields, and a certain commercial research centre was set up in the valleys of Somerset. Except it demonstrated the utilisation of heavy rates of fertiliser and how its always going to be greener on the otherside of a fence, especially where the farmer is applying 250 + units of nitrogen to the acre.
So the plant becomes “hydroponic” being fed via the artificial manure bag and looses the ability to feed itself. Where plants have been trialled in plant breeding stations for yield and protein content among other standards, they could have been testing their ability to grow unaided and sustainably in a healthy soil. You only have to look at the arable industry to see that wheat yields have plateaued, the only way considered to go is GMO. However, a few enlightened individual farmers are growing the old fashioned heritage varieties that produced adequate quanties of wheat from megre inputs. One of those inputs being straw shorteners, the result of having to mitigate the effects of high nitrogen applications, crazy. These varieties can easily grow and produce grains unaided using soil biology. Farmers fortunately now have other strings to their bows, with minimum or zero till sowing. Together with cover and companion crops they can now maintain soil health without fertility building leys. (IMHO by having to include these leys in a rotation are they not admitting that the other factors of the rotation are bad for the soil?)
Pic 3 An array of native plants (or weeds) that grew on the prairies and held the soil together prior to the over cultivations that lead to the Dust Bowl era.
Firstly, nature, as we know abhors a vacuum, so colonising plants whose job it is to get the biology functioning, ingress into any bare soil. These are often referred to, unkindly, as weeds.
Secondly, nature loves diversity and this biodiversity is where it gets interesting as the different plant roots interact with each other organisms to make the soil food web. The more species the more productive the field can be. We know that a balanced soil is best and that balancing comes from factors such as ratios of calcium to magnesium, carbon to nitrogen and most importantly fungi to bacteria. The last one being affected by our nutrient management and tillage as this can destroy fungi hyphae thus eliminating the important network of communication that enables all plants to thrive. Each species has different needs and draw on this hyphae to transport the necessary nutrients, that’s why soil that has grown a diverse mixture is healthier as it contains many more minerals and trace elements as well as a multitude of organisms.
So much for the status quo and excepted routes of learning from Agricultural establishments. In fact, I hear of Agricultural colleges having a major contract farming business take over the running of their in- house demonstration farming enterprises, a business not known for its diversity or biology farming, but for its rigid blueprints, reduced costs using buying group philosophy and huge land areas to dilute overhead costs.
If you grow a monoculture, and you talk of NP and K your job simple , simple results of stagnant arable yields as the input prices go up, and the promised meal ticket of increased yields has sadly left town, leading to a downward spiral of reduced farm profits.
All that technology, all that wisdom, knowledge and most of all chemistry gone into the oversimplification and crushing of soil biology.
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