Project Lamport update 3 - soil sampling

Project Lamport, now in its seventh year, is embracing digital for 2020. The team, including Head of Soils, Chris Martin; Farming Systems Research & Development Advisor, Niall Atkinson; Director of Wright Resolutions Ltd, Phillip Wright; and Independent (PhD) Researcher, David Purdy, will be sharing regular updates from the site in Northamptonshire. 

For our third blog update, Philip Wright and James Cheney take soil samples from various plots at Project Lamport, compare and discuss their findings. 

Director of Wright Resolutions Ltd, Phillip Wright

“The first sample we’re looking at is from a plot of traditional overwintered fallow which has been followed by spring wheat direct drilled with a Weaving GD. The soil has low porosity, is solid and dense with few visible pores. As a result, roots just aren’t getting through the soil profile. 

Absence of anything growing through winter into spring, plus heavy rainfall, has meant the soil has slumped - silt particles have filled the pores to form a solid mass.  

Benefits of a cover crop

Our next sample is from a plot which had an autumn cover crop established using a Weaving GD, this has been followed by a spring crop direct drilled again using the Weaving GD. Straight away we see considerably more roots than the first sample. 

It’s still reasonably low in porosity, but we can see developed roots from the crop. It’s also easier to pull the sample apart, and each time I find more roots. This clearly shows that the cover crop has worked and started to open the soil up, with the spring crop then following these channels. A clear example of the benefit of good rooting.

Finally, we look at a plot where we used a HE-VA subsoiler in autumn before broadcasting a cover crop onto the surface. This has been followed up by spring wheat. As I take the sample, you can already hear me breaking up the roots.

Deep root exploration

It’s much easier to break this sample apart, there’s visible porosity and the roots extend through. There’s almost a synergistic effect here – metal working alongside roots. Cultivating with metal has allowed the roots to get through, which has then helped the spring crop to exploit the structure and grow through at depth.

Metal doesn’t structure soil, roots do that. But sometimes we need metal to help roots along the way, as shown here. Part of the work at Project Lamport is to investigate just how much metal we need, how long for and how much we can reduce it.”

Agronomist and soil expert, James Cheney

“When we compare our first sample to the last sample, it becomes clear how really dense that first sample is. In comparison, the last sample is much more porous with strong rooting, where metal has allowed the roots to explore through.

Why have a cover crop?

Sometimes people ask me why do we need a cover crop at all? If you look at these soil samples, it’s like chalk and cheese – far greater rooting of the spring crop that follows the cover crop. 

For those using blackgrass as a ‘cover’, we can see blackgrass in our first sample and it’s barely rooted. I can pull it straight out meaning it’s had hardly any benefit on the soil.

This is why using a cover crop with good root mass makes all the difference.”