The first meeting hosted by David Blacker at his Skelton farm, looked at winter wheat and spring beans, both grown following the use of cover crops last autumn.

The wheat pictured below was in great health, with large flag leaves a good overall dark shade of green and no sign of stress or disease. With the flag leaf accounting for 75-80% of the final yield, keeping it clean is hugely important. The group discussed the importance of keeping crops clean from Septoria and rusts as even in resistant varieties, fighting disease takes up valuable energy and food from the crop, potentially limiting the final yield. If a lack of soil nutrients is limiting growth the plant will express these in a number of ways:

  • Magnesium deficiency will be expressed as pale striping on the older leaves
  • Manganese deficient crops will show yellow mottling on the flag leaf
  • Zinc deficiency can impede root development and reduce water uptake

 

 

David explained how the crop was established using a strip till drill, helping to improve soil structure with increasing amounts of organic matter and biological activity evident in the soil. This biological activity, up to two thirds from fungi, could result in 2000kg of biomass/Ha in healthy soil. The microbial mass along with a thriving worm population breaks down the plant debris in the soil. This respiration creates CO2 production, which permeates and is taken up by the crop via the canopy and the climate created at the base which helps to supercharge plant growth. The Group also viewed a crop of spring beans established using a strip till drill directly into the previous cover crop. David had done a simple trial looking at the impact of cover crop destruction timing on crop establishment using three different methods.

  1. Cover Crop was destroyed in the Autumn, all trash had gone by drilling and the crop was easily established, however, it was more damaged by pests and had a lot more weeds present.
  2. Drilled into green cover crop, which was sprayed off after drilling, this part of the field established a little slower but had less predation by flea beetles and fewer weeds. However, it did get some rook damage.
  3. The cover crop was destroyed 6 weeks before drilling. The crop established slightly quicker than that sown into the green cover crop but had some weed burden.

The crop of beans following all of the treatments looked very well.

 

 

The group discussed the ideal timing of cover crop destruction and how it often related to soil type and drainage. In poorly drained or wet soil, the green cover crop may make the top wet and greasy and hard to drill into, so earlier crop destruction would be beneficial. In free-draining soils, this is less important and later cover crop destruction is best to protect the soil, increase nutrient retention, accumulate more organic matter from the cover crop and improve soil structure.

As part of the Sustainable Landscapes Programme, soil samples were taken from each of the farmers’ best and poorest performing fields by Precision Decisions.

Neil Fuller discussed the analysis of the samples with the group. He pointed out that one of the key areas was the ability of soil to hold water and make that water available for plant growth. Soil is a mixture of sand, silt, and clay particles and that the proportion of these determines the characteristics of the soil.

When the soil reaches its saturation point, it holds 40- 45 % water. In 24 hours, this water drains away to what is called field capacity which varies for the different soil types. As the soil dries out the plant roots can no longer extract water and will start to die, this is called the wilting point. The difference between the field capacity and the wilting point is the available water, and it is this that the plant uses to grow. Neil explained how the available water differs between soil types.

 

 

Sandy soils only have 6% available water and therefore it is important to increase organic matter to act as a sponge to hold additional water. The careful use of Phosphorus to drive root mass and growth can also help. Silt soils have 20% available water, and clay soils hold significant amounts of water but this is held tightly and the wilting point can be at 30% soil water content. The use of manganese and zinc can stimulate root development, helping the plant to extract this water.

Increasing the organic matter content of soil improves the water holding capacity and therefore increases the amount of available water to help the crop to meet its potential. A Wheat crop requires 1000m3 of water to pass through it, to produce 1000kg of grain. With a low organic matter soil holding 180m3 of water/Ha, and a higher organic matter soil holding up to 600m3 of water/Ha, a small increase in organic matter can greatly increase the amount of available water, making the soil significantly more resilient and helping to increase crop yields.

Neil discussed how a visual soil assessment is important to determine, soil health. Poor draining soils have grey mottles as the iron content has been turned grey in anaerobic conditions and these conditions often produce Nitrous Oxide, a very serious greenhouse gas. This can be released from the soil and can account for as much as 60% of the carbon footprint of a crop even though it may only be 5-6kg/Ha.

 

 

Sustainable Landscape Meeting 15th May 2019
Elvington Pilot Site

The second meeting was held at the Hopwood family farm, Grimston Grange. The group were shown a field of spring barley where a cover crop had been grown over the winter. Half the cover crop was established using a drill the other half broadcasted and rolled. The broadcasted seed had not established well due to it being a very dry season. The cover crop that was drilled had established well and had grown a significant amount of organic matter.

The spring malting barley crop looked very well. Julian Hopwood explained how the field had FYM applied, was ploughed, furrow pressed and drilled using a disc drill. Where the cover crop had been well established the barley was a good green colour and showed no signs of stress or disease. However, where the cover crop had not established well there were signs of drought stress coming in and the crop on closer inspection had a yellow tinge.

The kit available for establishing cover crops was discussed and it was thought that an air drill attached to a cultivator such as a tillage train would give the best results for the least cost.

 

 

Neil Fuller discussed the soil profile and although the field had been ploughed the soil structure was good and there was a lot of new worm activity. There was as a great deal of organic matter visible, which would help to make the soil more resilient into the future.

Neil gave a presentation showing how farmers can increase the organic matter in soil by growing cover crops and non-inversion tillage. This upturn in organic matter will increase the organic carbon in the soil, helping to sequest carbon from the atmosphere. An increase of 0.04% of carbon in the agricultural soil over the next 20 years would bring atmospheric carbon dioxide down by 2-3 PPM and back to pre-industrial revolution levels.

 

 

Neil explained to the Group how there was a huge potential opportunity for farmers to earn additional income by farming more sustainably, either by meeting food company corporate responsibilities by growing lower carbon, more sustainable ingredients or by using their sustainable farming to create E credits to offset a company’s’ carbon footprint. He highlighted how large businesses are paying to offset the carbon produced by their activities and he believes that by changing land management practices on a landscape scale, farmers can not only help with climate change but also create an additional income in excess of the single farm payment.