Case Study: Sam and Claire Beaumont, Gowbarrow Hall Farm
Case Study: Sam and Claire Beaumont, Gowbarrow Hall Farm
Gowbarrow Hall Farm is an upland farm in the Lake District, run by Sam and Claire Beaumont and their family. They returned to the farm three years ago, which had been managed intensively by a local sheep grazier since the 1990s. Nitrogen was regularly used to improve the pasture, increasing grass growth which was cut and taken off the farm. Continuous fertiliser inputs and overgrazing disrupted the natural system, leading to a decline in soil biology, biodiversity and plantlife.
Sam and Claire have been working with Caroline Grindrod of Wilderculture to develop a blended regenerative and rewilding approach on the farm, to naturally regenerate the landscape. They gradually took back parts of the farm from the grazier, bringing in a small herd of Shorthorn cattle as well as a few Cumbrian Fell ponies and Kunekune pigs. They want to grow forage without inputs, using grazing and long rest periods, while restoring soil health, building biodiversity, and producing nutrient dense food.
Previously the sheep were grazing wood pasture in the parkland in summer, allowing hay to be cut on the meadows. This system was turned on it’s head with Caroline’s help; the cattle are now mob-grazed on the meadows in summer, and outwintered on standing hay in the wood pasture and woodland in the old parkland. The small number of fell ponies and pigs remain in the parkland all year round.
Claire and Sam are using Soilmentor to monitor their soil health and get instant feedback on how their management is supporting the awakening of soil organisms belowground.
Photo Credit: Anthony Cullen
“It was amazing to see the differences in the profile between the soil under hedgerows and the soil under pasture that has been over grazed for years. I saw a clear, dark topsoil layer in the hedgerow but out in the middle of the field the soil was yellow and there were no obvious layers. Doing VESS scores has been so interesting, looking closely at how the soil crumbles and even smelling it! We can already see a huge improvement in soil structure in the fields we’re mob grazing – it’s all down to rest.
Soilmentor is a great way to monitor what’s happening with our soil as it changes – we’re excited to see how it progresses. We love looking back at photos of our soil health on Soilmentor, and it is so useful to have the exact gps locations tagged for every soil sample site.”
Below is an example from their meadows of how the soil has changed since being rested in the winter and mob grazed in the summer. The left photo was taken in September 2019, and is noticeably more blocky than the right hand photo taken in October 2020. Bobbly, crumb like soil structure is appearing as the soil biology is being fed with manure and root exudates. Long rests allow the forage to grow up tall, not only providing more feed for the cattle, but also assisting the development of extensive root networks, increasing the capacity for nutrient exchange between the plants and the soil organisms.
The farm is beginning to regenerate naturally, as the soil biology and dormant seed bank start to awaken, allowing plants that have been overgrazed and outcompeted to spring into life. “We’ve got tons of forage now and we are seeing diversity return to the meadows. There is a lot more cocksfoot grass which has dense root networks and we are even seeing docks in a new light; they are excellent at breaking through compaction layers with their deep tap roots. We were thrilled to hear the call of a curlew when we stopped cutting the meadows for hay.”
In the parkland native wildflowers like Devil’s Scabious and tree saplings are popping up in the summer. Wildlife is moving in; little burrows are littered across the rough ground, and barn owls are returning to the farm.
We recently visited Gowbarrow Hall Farm for some soil testing with Caroline Grindrod – it was fantastic to see the natural regeneration first hand, and we look forward to following their regenerative journey.
Protected: Beneficial insect focus: Look after your beneficials over winter – Ben Harrington, Edaphos
Wet on Top — Dry Underneath – Guest Post by Niels Corfield
This is a guest post by Niels Corfield, Independent Farming Advisor and Educator. Learn about his courses here.
The winter of 2019/20 was challenging for farmers to say the least. Incessant rain meaning fields were not accessible, and winter crops were not sowed, large areas of flat or low lying country flooded (sometimes repeatedly) and otherwise generally redefining the concept of mud.
By springtime, what was the ground like out there? Wet, soft, or already hardening-up? Chances are it was the latter. So how can this be, after the wettest winter in living memory? When the ground across the farm (and the country), it seems, was saturated.
What if I said, that it’s the same root cause that produces both drought and flooding? That your farm, whether it be cropping or grazing, organic or conventional can be reworked to be both drought-proof and immune to extreme rain events. Sound too good to be true? Well read on.
If it’s not there when it’s wet, it’s not there when it’s dry
First we better rewind a few steps and show so how it is that a single causal factor is responsible for droughts and flooding.
This single causal factor means that on the one hand (in 2018) we were feeding-out first-cut silage and achieving little or no grain-fill and this winter we ended-up with maize harvests that looked like the battle of the Somme (reparable but not good optics).
Management Dictates Infiltration
Above we see two spade samples of the same soil type on the same day, margin on the left and grazed pasture on the right, recently reseeded.
Simply put, the causal factor is a lack of infiltration (or low infiltration rates) in all but the lightest or stoniest of soils — and a lack of water retention in these soils. The water that falls as rain has only one of two places to go – either into (and through) the soil OR away as runoff.
If your soil is very light or naturally free draining that water will go straight through, and in heavier soils that water will run-off. In both cases that water has left and has not been retained within the soil profile.
But our soils were clearly saturated this winter, I hear you say! How can you be suggesting there’s a lack of infiltration?
Well, the experience is, that it’s the surface of these soils that was at capacity, the bulk soil was dry, often very dry. See soil pictured below for an illustration.
You’ve got one chance, and one chance only, to get the water into your soil and that’s when it rains, as infiltration.
Without infiltration that water will run off. It’s a simple choice – where would we prefer to have our rainfall: in the soil where it can grow crops and forage, or in the valleys where it fills up like a bathtub: damaging property, and causing travel disruption and economic impact?
It seems counter-intuitive to say we want more water in our soils, given the experiences of winter we’ve just had. Surely, all that mud and saturation wants to be mitigated, by drainage or other means?
Well, no, in a word.
What we are looking for is deep penetration into – and through the soil profile.
So what does this mean? What is this indicative of?
Simply that these soils lack pore space. They often are blocky and consolidated and largely just structured in their “native”, mineral state (where all the soil particles are bonded to each other, in a tight crystalline state). These bonds are strong, but brittle, so when they fail, they may well “cleave” along fault lines, revealing: cracks, jagged edges and angular shapes.
At the landscape scale what features do we associate with these terms (and shapes)?
Generally: cliffs, rock faces, and mountains. And what is the study of these materials and these types of features? It’s geology.
Simply put, if your soil looks and behaves like geology: it shatters, cracks or cleaves, has the appearance of rocks or stone, it is geology.
Which makes sense because the sand, silt and clay is basically just ground up rock. However, when we refer to soil that’s just sand, silt and clay, it’s subsoil (in old money). Fundamentally, the difference between subsoil and topsoil is that topsoil is subsoil that has been acted upon by biology.
And what is biology’s influence on the soil structure? Primarily the creation of pore space. Converting the soil from its native, homogeneous state where the soil particles “pack” readily, into to a heterogeneous state, binding together disparate soil particles into crumbs or “aggregates” with a network of internal voids running between them.
Just as a biscuit maker converts base ingredients, flour and sugar, into crumbs with the addition of a binding agent, like butter. Where the flour and sugar particles are effectively the same size as one another, but once the binding agent is added those crumbs that result now have a large variation in size, from something like a bowling ball down to a golf ball.
In the case of the soil, our sugar is analogous to sand (coarse, granular), while the clay is analogous to flour (since if you purchase dried clay it comes bagged, as a powder). In soil, the aggregates are bound together by sticky substances like polysaccharides (carbohydrates) that are secreted by organisms like bacteria. In the same way that if you’ve ever got slug trail on your clothing it goes on sticky, cannot easily be washed off and sets hard, in other words these compounds are glue-like in nature.
So, we can say that soil aggregates are literally glued together by the secretions of biology.
This is what gives soil it’s friable crumbly and easily workable texture.
Fundamentally it’s this crumb structure and the pore space that facilitates infiltration. Over and above what the native soil does alone.
Moreover, with light soils these crumbs increase the surface area and with-it water holding capacity making them more moisture retentive. Since these surfaces of the aggregates are places where water films form. And it’s these billions of tiny water films throughout the soil volume that gives it its water holding capacity.
In heavy soils the opposite is the case, it serves to make the soil more free-draining. By opening up the dense structure and introducing pore spaces. Spaces that are interconnected, through which rainfall can easily percolate whilst also collecting around the aggregates as water films.
In both cases this forms a water reserve that can be drawn upon by crops and forages in the sunny, warm periods that are optimal for growth and grain fill.
So, with the exception of a small number of self-aggregating soils, crumb structure is entirely a product of biological activity and an expression of the carbon cycle in action, as these are carbon-based compounds, derived from plants, often root exudates (sugars).
It’s these processes at play in the above example comparing margin with reseeded pasture
Management Determines Infiltration Rates
So, what can you do, how can you achieve this friable structure without necessarily going to grass? Simply put, apply the soil health principles at every stage of your cropping and management practices.
Simply put here in the UK we are not victims of either too much or too little rainfall, just inadequate infiltration or retention. In a cropping situation it’s not only the lack of pore space but also surface capping (from rainsplash etc)
As Yoda might say:
“Hmm, not how much it rains that matters, how much we retain, it does.”
So in one fell swoop by fixing infiltration we not only do ourselves a favour: eliminating muddy conditions and poor field access options early and late season, we also optimise production through seasons like 2018.
Learn all about soil health and regenerative farming! Upcoming courses and workshops by Niels Corfield: Specialist Training courses for farmers, growers & land managers.
Courses focus on soil health and include specific courses for pasture, arable and horticulture. As well as regenerative grazing and whole farm planning.
All courses are now online.
Find out more HERE
Soilmentor makes it easy to monitor infiltration rates over time – discover how well your land is soaking up water now, and see how changes in management impact/improve infiltration rates (and other metrics!).
Soil Science Latest: How Can We Sequester More Carbon and Build Soil Health?
A few weeks ago we presented at Wageningen Soils Conference with Elizabeth Stockdale, Head of Farming, NIAB. We shared about the work we had done together converting the AHDB soils scorecard into an interactive Soil Quality UK Dashboard, with the main focus being “How can we get farmers talking about their soil health, based on soil health tests?”. We had lots of brilliant feedback about the dashboard we built and everyone at the conference was very positive as we talked about the benefits of a very different, more thoughtful, type of user research.
Whilst we were there we also listened to many brilliant talks sharing the latest soil science, some of which were incredibly relevant to the farming community, so we want to share the insights with you.
Building short-term vs long-term Carbon – it’s all down to the microorganisms!
We have all heard of words like humus, humic acid etc in terms of soils and carbon stored in soils. Well it turns out in the words of Johannes Lehman, soil scientist at Cornell University “humus is dead”.
He was very clear that it’s false to think there is such a thing as a long term carbon store that is locked up forever.
The idea that stored organic carbon can be neatly separated into 3 different types (Rapid, labile, stable), which has been the model for many years, is not reflected in the research any longer.
We shouldn’t worry about the idea of building long term carbon vs short term carbon, essentially all carbon that is sucked into the soil via photosynthesis or decaying organisms has the potential to become long-term carbon. What actually matters is which microorganisms are present and what they do with it.
There is no clear silver-bullet pathway to locking up carbon for good, instead we can think of soil organic carbon as an ongoing cycle of carbon gains and losses which we need to constantly manage. To many farmers this may not come as a surprise – that is exactly what we have seen happening in the field. As we practice more regenerative approaches (living roots in the soil, ensuring plenty of plant residues etc) we are quickly seeing the advantages of healthier soils which is so often synonymous with higher soil organic carbon and a more alive soil system (i.e more microorganisms).
Read more in this paper: Microbial models with minimal mineral protection can explain long-term soil organic carbon persistence
Dominic Woolf & Johannes Lehmann Scientific Reports volume 9, Article number: 6522 (2019)
Johannes showed that soil management techniques on farm to improve food security can have large beneficial effects on soil organic carbon. He drew from an example of changing agricultural practices in Ethiopia where they have been implementing agroforestry, diversified cropping systems, terracing, and many other agroecological practices — first and foremost as a measure to decrease poverty and prevent future drought scenarios. The project was undertaken on 600,000 Ha and had many benefits to the community, food security as well as environmental rehabilitation. However Johannes pointed out that it also had an unintended positive effect of sequestering significant amounts of carbon helping Ethiopia to meet their climate targets.
Read more in this paper: Land restoration in food security programmes: synergies with climate change mitigation
Dominic Woolf,Dawit Solomon &Johannes Lehmann Climate Policy Journal Pages 1260-1270 | Received 24 May 2017, Accepted 05 Jan 2018, Published online: 26 Jan 2018
Carbon Current Account and Interest Rates
We discussed these findings with Elizabeth Stockdale, Head of Farming at NIAB, and she gave the analogy that this implies we need to think of our soils like a current account – you are constantly making deposits and withdrawals of carbon, and that will be reflected in your carbon balance. From a farming perspective, what I wanted to know is what is the interest rate on this current account? That essentially would reflect how effective we will be in the long run at sequestering carbon in soils and building up our SOC. The banking analogy also makes a lot of sense, as it reflects the fragility of soil carbon in the face of larger scale disasters and fluxes in the market, as everything can be ‘lost’ at any time.
In summary Johannes Lehmann’s work showed that the focus of building soil organic carbon should be on farm ‘short-term’ carbon cycling interventions (e.g cover cropping, leaving plant residues, agroforestry, composting applications, rotational grazing) and the microorganisms will do the work to build longer term carbon deposits from there! Unfortunately this new understanding of soil organic carbon and the value of microorganisms has not been incorporated into IPCC models yet, so the value of these practices aren’t fully taken into account in global carbon targets…but Johannes said it will all change quickly.
Johannes also posited that the traditional models for understanding soil, based on adsorption and aggregation, although helpful in their way, are not necessary to explain soil organic matter and soil functioning. His work has shown that soil organic carbon and soil function can all be explained by the makeup of microorganisms and the action of microorganisms in the soil. It’s early days for fully understanding this as we still only understand around 5% of all the microorganisms in our soils!
The Soil Microbial Carbon Pump – how do microorganisms affect carbon storage in soils?
One model put forward for understanding the effect of microorganisms in sequestering carbon in soils was the Microbial Carbon Pump, explained by Chao Liang from the Chinese Academy of Sciences. The Soil Microbial Carbon Pump is a model for understanding how microbes are an active player in soil carbon storage. Chao showed how it could be applied at many different scales from the rhizosphere (plant root-soil interactions) to the field and landscape scale, which could have implications for understanding the responses of ecosystem carbon processes to global environmental changes.
My interpretation of what he was saying is that there are two types of carbon sequestration pathways through soil microorganisms:
- Biomass: The living biomass of the soil i.e living microorganisms taking carbohydrates being offered by plant roots and using it for food, excreting it in the form of slimes, building fungal hyphae etc. This is what Dr Christine Jones refers to as the liquid carbon pathway. (Catabolic pathway)
- Necromass: All the dead material, whether plant residues or compost materials etc being broken down and processed by microorganisms. Increasingly scientists are recognising the important role this plays in building soil organic matter. (Anabolic pathway)
Read more in this paper: The Importance of Anabolism in Microbial Control over Carbon Storage
Chao Liang, Joshua P. Schimel, Julie D. Jastrow Nature Microbiology volume2, Article number: 17105 (2017)
Chao showed how this model allowed them to investigate the effects of plant covers on microbial communities and what that meant in terms of the magnitude and composition of the soil carbon pool. He outlined that once the Microbial Carbon Pump processes carbon, it will either be released back to the atmosphere as CO2 – known as the priming effect (i.e decreasing the storage life of the carbon) or further increase the storage life of the carbon – known as the entombing effect. Their results showed that as the fungal proportion in the microorganism community increases the amount of carbon that goes through the entombing effect and becomes longer term carbon significantly increases after a certain time and then remains constantly high, whilst the priming effect although initially peaks, it then decreases and falls significantly below the entombing effect (you can see this in the photos below, where the high fungal content soil sample is the middle graph, highlighted in red)
Essentially what that means is that in soils with a higher proportion of fungi, the carbon is more likely to be turned into longer-life carbon deposits.
What does this mean for farmers?
The scientists are saying that yes it’s all about building microbial communities if you want to increase soil organic carbon.
There is no silver bullet, but it will take new management strategies based on careful monitoring of carbon gains and losses and making sure you are building more carbon on a field than you are taking away.
We can very much see ourselves as key actors when it comes to reducing greenhouse gas emissions and sequestering carbon at a global scale and that employing methodologies that improve soil health and soil microbial communities are the best way to do this. Of course, we already know this is what regenerative agriculture, conservation agriculture, permaculture and so many other farmer-led practices are all about! But it’s good to know the scientists are behind it all, and we hope this will enter the minds of the policy makers sooner rather than later!
We learned a lot from the conference and you will see some changes to Soilmentor in the coming months as we reflect some of our learnings to bring you some new tools to help you understand what your soil monitoring results mean.
Know your Soils #5: How well can your soil can hold onto nutrients?
Welcome to the fifth instalment of our Know your Soils series sharing practical tips for monitoring the soil health on your land. Keep an eye out for our bitesize videos and fact sheets on simple tests you can do yourself on farm.
“If you can’t measure it, you can’t improve it.”
Can your soil hold nutrients effectively?
A video from the ‘Learning from the Land’ series created by Catchment Sensitive Farming &Innovation for Agriculture
Earlier in the series, we discussed how rainwater can wash away all the precious nutrients in your soil, literally leaking money and resources down the field drains. Try this test at home to discover how good your soil is at holding onto different types of nutrients, specifically positively and negatively charged nutrients:
Making sure your soil has a stable structure and a high organic matter content is helpful for reducing nutrient loss. There are six basic soil health principles to follow to ensure your nutrients will not be lost with the next rainy day:
Living plants have living roots, they photosynthesise and transmit energy into the soil. This energy is feed for the beneficial soil organisms at work, creating aggregation in the soil.
It’s best to have living plants in the soil, as then you have living roots. But the next best thing is to ensure you cover ground with plant residue, e.g. with a terminated cover crop
Ploughing disturbs the soil organism population, preventing them from doing their necessary work to maintain healthy soil. Reducing cultivation or going no till keeps them happy!
A diverse range of plants in the soil means a diverse range of roots and a diverse diet for the soil organisms the roots are feeding. Roots have unique functions e.g tap roots bring nutrients up from deep in the sub soils and legume roots fix nitrogen directly in the soil.
Feeding the soil with compost, manure or compost tea will directly increase soil organic matter levels and provide plenty of food for worms!
Grazing livestock in a rotation is beneficial for increasing soil organic matter, terminating cover crops and decreasing weeds in your fields. Why not try mob grazing?
Minimise Chemicals & Synthetics
Adding chemicals can undo the good work you put in for the principles above — pesticides kill soil organisms, fertilisers make plants dependent and herbicides kill living roots.
There are a few bits of equipment you need to get together for this test, like ordering the dyes. How about doing it together with other local farmers so you can learn together which fields you are losing nutrients from?
- Soil samples
- Small jug
- Kitchen paper
- Polythene gloves
- Methylene blue dye
- Eosin dye
See our free online soils guide for soil tests you can do at home and find out how our app Soilmentor helps you record & learn how your soil is changing.
We are honoured to have Professor Jenni Dungait as a soils advisor and ambassador for Soilmentor. Jenni is a leading soil scientist, Editor in Chief for the European Journal of Soil Science and also offers brilliant insights into how soil works in the field through her consultancy Soil Health Expert. Find out more at www.soilhealthexpert.com
Our planet may be the only place in the universe where the conditions are right for soil to form. We rely on this miracle substance to grow our food, and it doesn’t usually let us down. So, most people, even some farmers, rarely think about the soil as more than ‘dirt’. But, relentless pressure over several decades to produce more and more food, with little regard for the effect of increasingly intensive agricultural production on soil, has taken its toll on this irreplaceable resource.
There is now real worry that the degradation of agricultural soils, combined with the changing climate and competition for agricultural land for other uses, will affect our ability to grow enough nutritious food in the future. Already, rarely a week goes by without reports in the media about food shortages caused by unpredictable extreme weather events and disease that are seriously affecting human well-being somewhere in the world.
Over the last couple of decades, I have devoted my life to discovering the science behind the remarkable ability of soils to keep on helping farmers to grow food, and what can be done when they don’t.
As a Professor of Soil Biogeochemistry working in world-renowned agricultural research institutes and universities, I have been lucky enough to travel across the world to talk to farmers about their soils and the problems that they are facing in the hope that scientific solutions can be developed.
There are some very common themes amongst concerns expressed by farmers that I have recognised across all continents.
- The weather is becoming more unpredictable, with droughts and flooding becoming more common.
- Yields are stagnant or declining despite using the latest crops, technology and agrochemicals which are all becoming more expensive.
- Breaking soil compaction is a major expense in time and money.
- Top soil losses in run off are causing local pollution problems.
- Weeds and disease are increasingly difficult to deal with.
- Falling farm incomes are forcing farmers to sell land for non-food production and construction.
- Farmers are expected to act as environmental stewards as well as producing food which seem to be opposing demands.
The innovative farmers who are successfully adapting to change and meeting these problems head on are those working in partnership with the life in our soils. These farmers say that getting the organisms in the soil to work with you is a win:win strategy that has reduced their workload and their expenditure on pesticides, fertilisers, irrigation, fuel and livestock medicines, whilst ensuring sustained yields and enabling them to meet their commitments to protect the environment. They recognise that Soil Health is the beating heart at the centre of their farming life.
Optimising Soil Health by managing the physics, chemistry and biology of agricultural soils is now recognised as a major part of the strategy for farmers to improve and sustain their businesses during the current period of intense change and to futureproof their livelihoods against the challenges to come.
What are the signs that soil is healthy? In recent years, I have been working with farmers’ groups in the UK and USA to find out which are the best and most reliable tests for Soil Health that can be easily used by farmers, but are also supported by the latest scientific evidence.
I am very pleased to be working as an independent Soil Health Expert with Vidacycle to develop the Soilmentor app using my knowledge. Watch out for a series of blogs from me on the Vidacycle website in the coming months, starting with ‘Soil Health – what’s it all about?’ as an introduction to the scientific basis for the individual soil health tests chosen for the Soilmentor app. If you have any questions you can email me at firstname.lastname@example.org.
The Soil Health Principles, thanks to soils advisor Niels Corfield:
Living Root – for as Long/as Often as Possible
Covered Soil – with Residues or Living Plants
Minimise Disturbance/Compaction – Tillage
Diversity – in Rotations/Plantings
Feed Soils – w/Organic Matter (Between Cropping)
Incorporate Animals – Ideally Adaptive Grazed
Minimise Use of Chemicals/Synthetics
The first thing to decide is where to do your soil tests. You might pick a few sample sites in 4 key fields and test them every 6 months. Most of these tests require a decent spade so you can dig 10-20cm depth into the soil profile in order to analyse it.
Soilmentor is made for farmers, to allow an understanding of the ‘pulse’ of the soils on their farm, so this is not a precise science – it’s about what works on your farm in order to monitor your soil health, better meet your management goals and ultimately have a thriving farm. So the key to all these tests is to be as consistent as possible with what works for you. We try to keep this as simple as possible to do, so for example, use a spades width and depth to ensure you dig up the same amount of soil each time you do your earthworm count, and use the same spade! Repeat the tests in the same field, at the same time of year (the app tracks this for you). Working with this simple principle you will build up an amazing picture of how your soil is changing, and hopefully improving!
We have more advice to help you make these decisions here.
1.The VESS test
This is where you get to dig in and really get a feel for your soil. We take a photo as soon as the soil is dug up to see its profile and initial structure (and so we can share it with others later to get their thoughts). Then we look to see if there is an obvious divide between a top soil and the subsoil below. On most farms we have visited the top layer of soil is as thin as 1-10 cm. This is where the aggregation* is happening and there are lots of roots so this is the layer we want to work on building up. Then the next 18cm is relatively uniform in colour and structure. We think it’s helpful to score topsoil and subsoil separately and record the depth of each – one indicator of better soil health is when the topsoil depth begins to increase, as roots reach further and further down and aggregation begins to happen deeper and deeper.
*aggregation: Soil aggregates are clumps of soil particles that are held together by moist clay, organic matter (like roots), gums (from bacteria and fungi) and by fungal hyphae. The aggregates are relatively stable and vary in size. This means that there are spaces of many different sizes in the soil and these spaces are essential for storing air, water, microbes, nutrients and organic matter.
Find full details about doing this test here.
2.Count your earthworms
Earthworms can be considered as the top of the soil food chain. They are engineers of their ecosystem, and provide some really amazing benefits to soil (learn more in our earthworm blog series here!). For this test, take the soil sample you’ve dug up and count how many earthworms are present. It’s important to note that this test is quite seasonal: on the farms we visited in the UK in November there were loads of earthworms but when we went out on the farm in Chile last week in the middle of Summer, we saw just one earthworm very deep, across 9 sample sites on 3 fields. When it is very dry earthworms tend to hide away! They also move around depending on heavy rains and other factors, so if you are going to do this test, then it’s best to do it across all the fields you are monitoring in one go. That way you can compare between fields.
Find full details about doing this test here.
3.The Slake test
This test is very easy to do – you just put a large pea-sized piece of soil in water and leave it. How much the ‘pea of soil’ breaks down indicates how much sticky stuff there is holding your soil together, thanks to the work of all those little microbes. Our three fields had soils that broke down completely differently. In one field where there was the most evidence of aggregation, the ‘pea’ did not break down at all over 24 hours. However, in another field, where the soil was very crumbly, red and easy to dig into but also not much evidence of structure, most of the samples broke down completely within 2 hours and all within 24 hours. As far as I understand this shows that the microbial activity and aggregation activity is very low in this soil. It was deep-ploughed somewhat recently which may explain the lack of compaction but its lack of aggregate structure suggests it’s lacking biological activity.
Find full details about doing the test here.
4.How much ground cover and bare soil is there? What is the percentage cover of weeds (undesirables), herbs, grasses?
For many of us, a key reason healthy soils is important is because we want healthy plants above ground, and importantly healthy plants that support the bottom line. For PFLA members that often means increased forage, more grass species, less buttercups. On our farm in Chile that means healthy vines and olives, and fostering warm season grasses and perennials for fire retardant ground cover in Summer.
This measure is a great way to understand the link between healthy plants and healthy soils. The 1st soil health principle is a living root, so lots of bare soil is not a good sign. What’s on the surface of our soils can tell us a lot about what is happening below, so for this test record % cover of undesirable species, herbs, grasses and bare soil. Our farm is not pasture-based but this is still helpful as a measure – one of our main tools for managing damage from fires is to shift our ‘undesirables’ to plants that remain green all Summer long.
To do this test you need to make yourself a quadrat. Full details on doing these tests here.
5.Measure the sugar content and health of your groundcover with a Brix reading
Brix is a measure of photosynthetic activity. The building block for production and plant immunity/health. Brix measures how much photosynthesis is occuring in the plant by showing the amount of sugar and dissolved solids in the sap. Higher values indicate the plant is photosynthesizing more rapidly, therefore growing faster, with a better immune response and a higher nutrient profile. Brix is already used by many fruit producers as an indicator of when their fruit is ready to harvest. Research has shown that Brix readings show the actual sugar content in pasture, as well as other plants.
I first heard about it from Australian farming advisor Graeme Saite as he explained if you take a Brix reading in the morning and then another in the afternoon, there should be a big difference in sugar content because late afternoon the plant moves all its sugar from its leaves (solar cells) to its roots to converse with the world below. If this isn’t the case then the system connecting your plant to the soil isn’t working.
We mainly use Brix as an indicator of plant health. We compare Brix readings across fields at the same time to see which plants have more sugars. It’s then interesting to do see how the Brix value evolves over time. An increase in Brix value could be a good indicator of improvements in soil health and healthier plants. Brix is very dependent on the time of day you do it (as explained above) as well as the season, so if you want to compare across fields you need to get round and do the Brix readings all in one go and then try to do them again, on more or less the same day and time a year later. Also, Brix doesn’t work in wet conditions as the rainwater dilutes the reading.
To perform a brix test you will need a refractometer and garlic crusher. Find full details on how to do this test here.
So, those are some ideas of soil tests to get you started! Keen to learn a few more? Head over to the free soil testing guide on our website to check out the full list, record some wildlife with the biodiversity tool, and learn more about our Soilmentor app here.
Sunday morning early my dad and I went out to observe and investigate our soils on our farm in Chile. As you may know 2017 was a very difficult year for my family’s small farm as the mega fires in Chile consumed our farm, burning all our crops — olives and vines, just the buildings survived. Come November (Spring) it became obvious that most of the 8000 olive trees and 2ha of vines were dead or growing back from the ground. In terms of having a crop, it’s a bit like starting again.
It is at times an overwhelmingly dire situation. But there is no point lingering on the negatives as this is what’s happened and mega fires are bound to happen again based on global trends, so we must rethink.
Where to start? The soils. If there is one thing I have learnt over the last year, it’s that soil health is the litmus test for the direction your farm is going in. For fire prevention we see two ways forward: Either we bite the bullet and plough between all the trees and build fire breaks around the whole farm (100m wide!?) — a disaster for soil health; Or, we make our 700ml of rainfall each winter go further and retain moisture on as much of the farm as possible, for as long as possible, allowing a green ground cover all year round. Neither sounds particularly easy, but as the realities of the changing climate and human impact on our landscapes intensify — we have little choice. So we are opting for the latter, as the first sounds like a barren nightmare.
To systematically observe our soils and document where we are at now we used Soilmentor, an app I recently launched, along with the Pasture-Fed Livestock Association and soils advisor Niels Corfield. I’ve used the app on a number of other farms in the UK, but this felt like a seminal moment using it on our own farm in Chile for the first time. This app is just part of my commitment to ensuring smaller-scale farming businesses around the world thrive, building a more resilient future for us all. In an odd way, it felt very moving to have this tool support our farm, especially at this moment of so many unknowns! I can’t explain but when you go out and really observe the soil, something happens, you become immersed in a whole new dimension of the farm.
Back to our farm. Doing the tests. We went to 3 fields and dug a hole as best we could at 3 sites in each field. At first it felt incredibly daunting looking at the different tests in the app. I am still learning about soil science, so many things I don’t know! How deep should we dig? How many samples should we take? How can we tell where the top layer of soil ends and the bottom one begins for the VESS (Visual Evaluation of Soil Structure) test? And in fact how can we determine aggregates* from clods* in this incredibly arid soil? Luckily many of those questions are answered here.
We gave it our best shot, followed the notes on the VESS diagram and gave the top layer of soil a slightly higher score than the bottom, determining it was just 1cm deep — that’s where almost all of the roots were and some evidence of aggregation. We had to use a hammer to cut down into the soil, so Spading Ease was definitely 1 (the worst). As we moved on to the next hole it got easier to assess VESS and by Sector 2 we felt confident scoring our soil. Here, in Sector 2, things were quite different, the top 5–6 cm were top soil and showed definite signs of aggregation but then beyond 6cm the ground was almost impenetrable. In Sector 7, we were amazed the spade went in easy after the initial top cm or so. It was completely different again, a crumb-like soil all the way down, quite red, but oddly little sign of microbial life or root activity.
For each VESS reading we took two photos of the soil, one before breaking it up and one after. Later this week I will be talking through the results and photos with soils advisor Niels Corfield in the UK to better understand what it all means and how we might move forward in terms of management. Pretty exciting that we can so easily share the state of our soils with an advisor.
We brought back samples from each field and did a slake test, Sectors 1 and 7 mainly disintegrated but as expected those from the top layers of Sector 2 stayed glued together. I did question whether the slake test would work for such dry soils, maybe they wouldn’t break down because they are baked into shape…or they would disintegrate completely because they have no moisture in them to keep their shape? Always so many questions and variables. But as we looked over the tests 24 hours later it seemed pretty obvious. Only Sector 2 had any real sign of the soil being stuck together thanks to microbial and root slimes (good stuff!) — it stayed completely intact. Sector 1 disintegrated partially and Sector 7 completely disintegrated. An interesting indication that the light crumbly soil in Sector 7 probably isn’t thanks to great soil creation from plants and microbes but a combination of other factors in the short term (it was dug up most recently of the 3). But I’m not sure on this one so will be asking in the group convo what others think!
The whole experience was rather brilliant, my dad and I in conversation about our soils, really looking and recording whilst we go. We now have begun to understand what we are working with and that the mechanism for living soils is not currently in action on our land. The next step is how to get that mechanism in action as soon as possible. Currently we are considering direct drilling with multi-species herbal leys, grazing lambs in Spring, or maybe chickens all year round. We also want to use compost teas to move the soil health more quickly, as a short term input. If you have any other suggestions please let us know 🙂
How will we test if things are getting better? Well if our VESS top depth begins to increase and the score goes up in the bottom layer, if we start to see rhizosheaths, if we have even one or two earthworms and if we have all 3’s on the slake test then we will know our soil health is improving — it seems like a huge challenge but we believe it’s possible. Let the work begin!
Soilmentor is now available for anyone to use to investigate and monitor their own soils — find out more here. Join a community of farmers working together to monitor our soils and improve soil health!
*A few soil words:
- aggregation: Soil aggregates are clumps of soil particles that are held together by moist clay, organic matter (like roots), gums (from bacteria and fungi) and by fungal hyphae. The aggregates are relatively stable and vary in size. This means that there are spaces of many different sizes in the soil and these spaces are essential for storing air, water, microbes, nutrients and organic matter.
- clods: Soil clods are clumps of soil stuck together due to compaction. They often have very few spaces in them and can be very large. A sign of not as good soil health.