Project Lamport 2020

For our sixth blog update, Niall is joined by Technical Manager Mark Hemmant, to discuss R&D at Project Lamport.

Technical Manager, Mark Hemmant

“For Project Lamport, we don’t want to reinvent the wheel. Investigating seedbed nitrogen and nitrogen dose response work in blackgrass situations has all been done. As spring cereals become more dominant in rotations, our new challenge is to see how we can drive them forward most effectively.

A lot of this lies in soil health. But, in order to make our work relevant to growers across the country, we recognise that our R&D shouldn’t just be about the soils at Lamport.

Starting with Project Lamport where we have high calcareous soil, our work has shown that adding something to release phosphorus is really important, as these soils ‘lock’ it up. If phosphorus is locked up, it won’t be available to the crop.

In contrast, where we have high magnesium soils, we have been investigating the benefits of applying a liquid gypsum product - a useful nutrition source of calcium and sulphur. This helps to not only improve soil structure, but also balances calcium-magnesium ratios.

By improving soil health and making nutrition more freely available, we can reduce the reliance on traditional crop protection products and use them more efficiently.

We also have some exciting pipeline projects, one of which looks at if we can remove metal completely. An example here at Project Lamport is where we broadcast cover crop seed into the standing crop, followed by direct drilled spring wheat. The aim of this is to truly maximise soil health, and we hope to investigate this further.

Another aim is to have a permanent under-sowing of clover in a spring cereal plot. This will enable us to look at weed suppression potential as well as additional soil fertility benefits of legumes.

Because growing a successful crop of oilseed rape is often hindered by flea beetle, our R&D plans also include trying alternative establishment methods for OSR and winter linseed on heavy soils with blackgrass pressure.

Pushing our R&D and Project Lamport forward is vital in enabling us to provide growers with new and innovative solutions that work in a practical situation.”

For the fifth blog update, wider members of the Agrovista soil heath team interview our Lamport experts to ask the questions that you’re likely to have.

Is the choice of cover crop important?

Head of Soils, Chris Martin

“Blackgrass control certainly influences the species of cover crop we should use prior to a spring crop. It’s important to select a slow growing species that allows blackgrass to grow amongst it so it’s trapped. Then, when the cover crop, ie black oats and phacelia, gets growing later in the season, it develops a lot of bulk below ground. This dries out the soil allowing us to direct drill efficiently in the spring

If we wanted more diversity or a thicker cover crop, we wouldn’t achieve the same success with blackgrass control. So yes, blackgrass control really is influenced by selecting the correct cover crop.”

Are all black oat varieties the same?

Chris Martin

“Black oats are fundamental to the success of Project Lamport but they do vary significantly in vigour and heading date. We should be looking for a variety that doesn’t set seed and become a weed itself. If chosen correctly, the main benefit is root mass and where we have roots we have improved soil biology. Late heading varieties will also have the advantage of a lower C:N ratio – reducing any potential adverse effect on cash crop, if for instance destruction timing is delayed.”

What are the best ways to establish a cover crop?

Farming Systems Research & Development Advisor, Niall Atkinson

“What we’ve used with great success is the Vaderstad CrossCutter to premix residues and create a fine shallow tilth. Cover crop seed could then either be applied off the back of the Crosscutter, or as a separate operation. By working with this machine at a shallow 1-2” depth, we are allowing blackgrass to easily grow among the cover crop.

At Lamport we have followed the Crosscutter with both a combi drill and a cultivator drill for a direct comparison. Having successfully direct sown our covers, good residue management is essential with this technique. We’re also regularly asked about soil loosening and my default is to move the soil as little as possible below ground. This is because we know that the more we move the soil, the more we mix grass seed through the soil profile. My judgement for this is the previous crop – if we’ve harvested a good yield then there is likely very little wrong with that field. As long as we manage our harvest traffic it should be structurally sound requiring only shallow cultivations.

If we want to use metal to compliment the roots, we’ve found that using a low disturbance soil loosener similar to what is used to establish oilseed rape is best. But, our default at Lamport is no metal in order to benefit soil health.

We are also experimenting with broadcasting covers direct into the crop prior to harvest. This is the ultimate technique - timely low-cost establishment with nil soil movement.

Do you have thoughts on successfully destroying a cover crop?

Chris Martin

“Whilst the cover crop might successfully be controlled by grazing or mechanical means; for blackgrass we have to consider glyphosate and timing is key. When using a cover crop for blackgrass control, we need to destroy it early around January time. When we’ve done this at Lamport we’ve achieved 0.5t/ha increase in the following crop yield, compared to those after a later cover crop destruction. This is because it allows the soil to dry out as well as achieve greater success with the direct drill. It also encourages biomass to decompose and nutrients to mineralise and become available for the spring crop. Later destructions can have the opposite effect by immobilising nutrients. So for blackgrass control, we recommend earlier destruction.”

Any tips for drilling the spring crop?

Niall Atkinson

“One thing that we learned through our mistakes is how important the direction of drilling is. Going at 90 degrees to the direction of the cover crop creates more soil movement. So a key learning is that you must drill the cover crop in the same direction to what you intend to drill your spring crop.

Choosing row width is also important. Wider row spacing isn’t necessarily the best for the systems we have at Lamport. Most of our work is with drills working at 160-170mm spacing and we’ve learnt this because where we’ve had wider wheelings, we’ve found blackgrass. That tells us that we need good crop competition there. If you were drilling into late destroyed bulky covers, you might struggle to get flow through the drill with a very narrow spacing. So 160-170mm seems to suit us best.

That leads onto seed rates which are critical. Here at Lamport our best establishment rate for spring wheat has been around 65-70%. That means if we used 250-300 seeds per m2 we’d likely have poor crop competition. So we’re up to 500 seeds per m2 for spring wheat and 450 seeds per m2 for spring barley.”

Do you think this system could work for other spring crops?

Niall Atkinson

“Judging by this crop of spring oats I would say yes it does work. Here we’ve needed no grass weed pre-ems so I think it’s safe to say that Project Lamport has taught us how to successfully grow spring crops on heavy land.

After seven years with all of the conditions possible thrown at us, we always get the job done.”

Head of Research and Development, Craig Morgan

“Ultimately, we want to successfully grow a spring crop here at Project Lamport whilst fostering soil health. During the seven years we’ve been doing this, on average we’ve achieved 7-7.5t/ha. This has ranged from 8.5t/ha in the better crops, down to 6.5t/ha.

We began Lamport on a quest to reduce blackgrass and we achieved this from the moment we implemented cover crops. We’ve come down from 2000 heads/m2 to 3-4 heads/m2 because our systems are so effective, as demonstrated here.

For system 3, we established an autumn cover crop using a combi drill followed by a direct drilled spring wheat. Although the subsequent crop has established well, it hasn’t offered much in terms of soil health.”

Director of Wright Resolutions Ltd, Phillip Wright

“The soil sample for system 3 shows a tight top layer, which is often indicative of a power harrowing action. The structure has been stirred and destabilised, then the deluge of rain last year has washed the high silt content of the clay soil together, causing a slumping effect.

We have some roots at depth, but not many and most are in the surface layer. It’s an effort to break the sample apart and we have a consolidated profile with not much pore space or root pathways.”

Farming Systems Research & Development Advisor, Niall Atkinson

“In contrast, system 4 is a cover crop established using a direct drill to avoid soil damage. We have learnt our lesson that a combi drill just doesn’t offer much towards soil health.

So we ask the important question - ‘How do we establish a cover crop without soil damage?’ Part of the answer is when direct drilling, residue management of the previous crop needs to be tip top.

Here, we straw raked before going over with a Weaving GD to direct drill. The results are reasonable cover crop establishment, low levels of blackgrass and much improved soil health.

System 7, which is spring wheat following a traditional over-wintered fallow, demonstrates the value of the cover crop. We have greater counts of blackgrass which will have only increased by July.

By carefully selecting species depending on the scenario, you can achieve so many benefits from cover crops. We learnt earlier in the year that by using black oats, water infiltration is improved and standing water reduced. This is because of the fantastic root structure that that particular species offers.

And selecting different species of cover crops can also enhance your rotation, introducing crops such as phacelia, linseed and vetches. So although you are regularly growing spring cereals, it’s the cover crops that are providing the diversity.”

Philip Wright

“Because system 7 had quite an aggressive cultivation in autumn and no cover crop, it’s a good example to share as we are almost back to square one from a soil health perspective. With no root activity, it shows the synergistic effect of roots and metal. We can cultivate, but we need the roots to create the actual structure.

This sample has low porosity and is very hard to break apart and we have blackgrass starting to creep back in.”

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.”

For our second blog update, Chris Martin discusses some of the soil health benefits seen at Project Lamport, as well as the impact of cultivating with metal.

“Having successfully controlled blackgrass over the years at Lamport, we’ve seen that the methods used have also had a really positive impact on our soils. 

For example, increasing the diversity of species and time of cropping has had a big impact on soil biology. Whereas introducing spring cropping, particularly after cover cropping, has had a positive effect on general soil health.

Black oats in the rotation

We’ve seen this on a practical level in the field in that by using black oats in the rotation, we have increased our microbial biomass and respiration levels. We’ve also measured high numbers of earthworms associated with the black oats, prior to spring cropping. This is because black oats have a huge rhizosphere, or root mass, compared to other cover crops. 

Ultimately, we want to build a ‘hotel’ for our soil biology to live in. Each time we cultivate, we potentially rip through the hotel we’ve built. So, we want to try to move as little through the soil with metal as possible, to allow roots to do this naturally instead. 

Minimising soil disturbance

Our default setting is to not move the soil at all, and have a valid reason to do so before we do so. Also, every time we use metal in the soil we oxidise carbon, losing it to the atmosphere as well as organic matter from the soil.

When we do use metal, we must ensure that machinery is well balanced, putting as little pressure onto the soil so not to squash the soil biology. Select the lowest tyre pressure for the operation, allowing soil to naturally structure itself without hindrance. 

Lamport has taught us to ask the question – do I have a grass weed problem, or do I have a system problem that allows weeds such as blackgrass to thrive? Improving soil health is starting to answer those questions for us.